1 /*
2  * MSM 7k/8k High speed uart driver
3  *
4  * Copyright (c) 2007-2011, Code Aurora Forum. All rights reserved.
5  * Copyright (c) 2008 Google Inc.
6  * Modified: Nick Pelly <npelly@google.com>
7  *
8  * This program is free software; you can redistribute it and/or
9  * modify it under the terms of the GNU General Public License
10  * version 2 as published by the Free Software Foundation.
11  *
12  * This program is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
15  * See the GNU General Public License for more details.
16  *
17  * Has optional support for uart power management independent of linux
18  * suspend/resume:
19  *
20  * RX wakeup.
21  * UART wakeup can be triggered by RX activity (using a wakeup GPIO on the
22  * UART RX pin). This should only be used if there is not a wakeup
23  * GPIO on the UART CTS, and the first RX byte is known (for example, with the
24  * Bluetooth Texas Instruments HCILL protocol), since the first RX byte will
25  * always be lost. RTS will be asserted even while the UART is off in this mode
26  * of operation. See msm_serial_hs_platform_data.rx_wakeup_irq.
27  */
28 
29 #include <linux/module.h>
30 
31 #include <linux/serial.h>
32 #include <linux/serial_core.h>
33 #include <linux/tty.h>
34 #include <linux/tty_flip.h>
35 #include <linux/slab.h>
36 #include <linux/init.h>
37 #include <linux/interrupt.h>
38 #include <linux/irq.h>
39 #include <linux/io.h>
40 #include <linux/ioport.h>
41 #include <linux/kernel.h>
42 #include <linux/timer.h>
43 #include <linux/clk.h>
44 #include <linux/platform_device.h>
45 #include <linux/pm_runtime.h>
46 #include <linux/dma-mapping.h>
47 #include <linux/dmapool.h>
48 #include <linux/wait.h>
49 #include <linux/workqueue.h>
50 
51 #include <linux/atomic.h>
52 #include <asm/irq.h>
53 
54 #include <mach/hardware.h>
55 #include <mach/dma.h>
56 #include <linux/platform_data/msm_serial_hs.h>
57 
58 /* HSUART Registers */
59 #define UARTDM_MR1_ADDR 0x0
60 #define UARTDM_MR2_ADDR 0x4
61 
62 /* Data Mover result codes */
63 #define RSLT_FIFO_CNTR_BMSK (0xE << 28)
64 #define RSLT_VLD            BIT(1)
65 
66 /* write only register */
67 #define UARTDM_CSR_ADDR 0x8
68 #define UARTDM_CSR_115200 0xFF
69 #define UARTDM_CSR_57600  0xEE
70 #define UARTDM_CSR_38400  0xDD
71 #define UARTDM_CSR_28800  0xCC
72 #define UARTDM_CSR_19200  0xBB
73 #define UARTDM_CSR_14400  0xAA
74 #define UARTDM_CSR_9600   0x99
75 #define UARTDM_CSR_7200   0x88
76 #define UARTDM_CSR_4800   0x77
77 #define UARTDM_CSR_3600   0x66
78 #define UARTDM_CSR_2400   0x55
79 #define UARTDM_CSR_1200   0x44
80 #define UARTDM_CSR_600    0x33
81 #define UARTDM_CSR_300    0x22
82 #define UARTDM_CSR_150    0x11
83 #define UARTDM_CSR_75     0x00
84 
85 /* write only register */
86 #define UARTDM_TF_ADDR 0x70
87 #define UARTDM_TF2_ADDR 0x74
88 #define UARTDM_TF3_ADDR 0x78
89 #define UARTDM_TF4_ADDR 0x7C
90 
91 /* write only register */
92 #define UARTDM_CR_ADDR 0x10
93 #define UARTDM_IMR_ADDR 0x14
94 
95 #define UARTDM_IPR_ADDR 0x18
96 #define UARTDM_TFWR_ADDR 0x1c
97 #define UARTDM_RFWR_ADDR 0x20
98 #define UARTDM_HCR_ADDR 0x24
99 #define UARTDM_DMRX_ADDR 0x34
100 #define UARTDM_IRDA_ADDR 0x38
101 #define UARTDM_DMEN_ADDR 0x3c
102 
103 /* UART_DM_NO_CHARS_FOR_TX */
104 #define UARTDM_NCF_TX_ADDR 0x40
105 
106 #define UARTDM_BADR_ADDR 0x44
107 
108 #define UARTDM_SIM_CFG_ADDR 0x80
109 /* Read Only register */
110 #define UARTDM_SR_ADDR 0x8
111 
112 /* Read Only register */
113 #define UARTDM_RF_ADDR  0x70
114 #define UARTDM_RF2_ADDR 0x74
115 #define UARTDM_RF3_ADDR 0x78
116 #define UARTDM_RF4_ADDR 0x7C
117 
118 /* Read Only register */
119 #define UARTDM_MISR_ADDR 0x10
120 
121 /* Read Only register */
122 #define UARTDM_ISR_ADDR 0x14
123 #define UARTDM_RX_TOTAL_SNAP_ADDR 0x38
124 
125 #define UARTDM_RXFS_ADDR 0x50
126 
127 /* Register field Mask Mapping */
128 #define UARTDM_SR_PAR_FRAME_BMSK        BIT(5)
129 #define UARTDM_SR_OVERRUN_BMSK          BIT(4)
130 #define UARTDM_SR_TXEMT_BMSK            BIT(3)
131 #define UARTDM_SR_TXRDY_BMSK            BIT(2)
132 #define UARTDM_SR_RXRDY_BMSK            BIT(0)
133 
134 #define UARTDM_CR_TX_DISABLE_BMSK       BIT(3)
135 #define UARTDM_CR_RX_DISABLE_BMSK       BIT(1)
136 #define UARTDM_CR_TX_EN_BMSK            BIT(2)
137 #define UARTDM_CR_RX_EN_BMSK            BIT(0)
138 
139 /* UARTDM_CR channel_comman bit value (register field is bits 8:4) */
140 #define RESET_RX                0x10
141 #define RESET_TX                0x20
142 #define RESET_ERROR_STATUS      0x30
143 #define RESET_BREAK_INT         0x40
144 #define START_BREAK             0x50
145 #define STOP_BREAK              0x60
146 #define RESET_CTS               0x70
147 #define RESET_STALE_INT         0x80
148 #define RFR_LOW                 0xD0
149 #define RFR_HIGH                0xE0
150 #define CR_PROTECTION_EN        0x100
151 #define STALE_EVENT_ENABLE      0x500
152 #define STALE_EVENT_DISABLE     0x600
153 #define FORCE_STALE_EVENT       0x400
154 #define CLEAR_TX_READY          0x300
155 #define RESET_TX_ERROR          0x800
156 #define RESET_TX_DONE           0x810
157 
158 #define UARTDM_MR1_AUTO_RFR_LEVEL1_BMSK 0xffffff00
159 #define UARTDM_MR1_AUTO_RFR_LEVEL0_BMSK 0x3f
160 #define UARTDM_MR1_CTS_CTL_BMSK 0x40
161 #define UARTDM_MR1_RX_RDY_CTL_BMSK 0x80
162 
163 #define UARTDM_MR2_ERROR_MODE_BMSK 0x40
164 #define UARTDM_MR2_BITS_PER_CHAR_BMSK 0x30
165 
166 /* bits per character configuration */
167 #define FIVE_BPC  (0 << 4)
168 #define SIX_BPC   (1 << 4)
169 #define SEVEN_BPC (2 << 4)
170 #define EIGHT_BPC (3 << 4)
171 
172 #define UARTDM_MR2_STOP_BIT_LEN_BMSK 0xc
173 #define STOP_BIT_ONE (1 << 2)
174 #define STOP_BIT_TWO (3 << 2)
175 
176 #define UARTDM_MR2_PARITY_MODE_BMSK 0x3
177 
178 /* Parity configuration */
179 #define NO_PARITY 0x0
180 #define EVEN_PARITY 0x1
181 #define ODD_PARITY 0x2
182 #define SPACE_PARITY 0x3
183 
184 #define UARTDM_IPR_STALE_TIMEOUT_MSB_BMSK 0xffffff80
185 #define UARTDM_IPR_STALE_LSB_BMSK 0x1f
186 
187 /* These can be used for both ISR and IMR register */
188 #define UARTDM_ISR_TX_READY_BMSK        BIT(7)
189 #define UARTDM_ISR_CURRENT_CTS_BMSK     BIT(6)
190 #define UARTDM_ISR_DELTA_CTS_BMSK       BIT(5)
191 #define UARTDM_ISR_RXLEV_BMSK           BIT(4)
192 #define UARTDM_ISR_RXSTALE_BMSK         BIT(3)
193 #define UARTDM_ISR_RXBREAK_BMSK         BIT(2)
194 #define UARTDM_ISR_RXHUNT_BMSK          BIT(1)
195 #define UARTDM_ISR_TXLEV_BMSK           BIT(0)
196 
197 /* Field definitions for UART_DM_DMEN*/
198 #define UARTDM_TX_DM_EN_BMSK 0x1
199 #define UARTDM_RX_DM_EN_BMSK 0x2
200 
201 #define UART_FIFOSIZE 64
202 #define UARTCLK 7372800
203 
204 /* Rx DMA request states */
205 enum flush_reason {
206 	FLUSH_NONE,
207 	FLUSH_DATA_READY,
208 	FLUSH_DATA_INVALID,  /* values after this indicate invalid data */
209 	FLUSH_IGNORE = FLUSH_DATA_INVALID,
210 	FLUSH_STOP,
211 	FLUSH_SHUTDOWN,
212 };
213 
214 /* UART clock states */
215 enum msm_hs_clk_states_e {
216 	MSM_HS_CLK_PORT_OFF,     /* port not in use */
217 	MSM_HS_CLK_OFF,          /* clock disabled */
218 	MSM_HS_CLK_REQUEST_OFF,  /* disable after TX and RX flushed */
219 	MSM_HS_CLK_ON,           /* clock enabled */
220 };
221 
222 /* Track the forced RXSTALE flush during clock off sequence.
223  * These states are only valid during MSM_HS_CLK_REQUEST_OFF */
224 enum msm_hs_clk_req_off_state_e {
225 	CLK_REQ_OFF_START,
226 	CLK_REQ_OFF_RXSTALE_ISSUED,
227 	CLK_REQ_OFF_FLUSH_ISSUED,
228 	CLK_REQ_OFF_RXSTALE_FLUSHED,
229 };
230 
231 /**
232  * struct msm_hs_tx
233  * @tx_ready_int_en: ok to dma more tx?
234  * @dma_in_flight: tx dma in progress
235  * @xfer: top level DMA command pointer structure
236  * @command_ptr: third level command struct pointer
237  * @command_ptr_ptr: second level command list struct pointer
238  * @mapped_cmd_ptr: DMA view of third level command struct
239  * @mapped_cmd_ptr_ptr: DMA view of second level command list struct
240  * @tx_count: number of bytes to transfer in DMA transfer
241  * @dma_base: DMA view of UART xmit buffer
242  *
243  * This structure describes a single Tx DMA transaction. MSM DMA
244  * commands have two levels of indirection. The top level command
245  * ptr points to a list of command ptr which in turn points to a
246  * single DMA 'command'. In our case each Tx transaction consists
247  * of a single second level pointer pointing to a 'box type' command.
248  */
249 struct msm_hs_tx {
250 	unsigned int tx_ready_int_en;
251 	unsigned int dma_in_flight;
252 	struct msm_dmov_cmd xfer;
253 	dmov_box *command_ptr;
254 	u32 *command_ptr_ptr;
255 	dma_addr_t mapped_cmd_ptr;
256 	dma_addr_t mapped_cmd_ptr_ptr;
257 	int tx_count;
258 	dma_addr_t dma_base;
259 };
260 
261 /**
262  * struct msm_hs_rx
263  * @flush: Rx DMA request state
264  * @xfer: top level DMA command pointer structure
265  * @cmdptr_dmaaddr: DMA view of second level command structure
266  * @command_ptr: third level DMA command pointer structure
267  * @command_ptr_ptr: second level DMA command list pointer
268  * @mapped_cmd_ptr: DMA view of the third level command structure
269  * @wait: wait for DMA completion before shutdown
270  * @buffer: destination buffer for RX DMA
271  * @rbuffer: DMA view of buffer
272  * @pool: dma pool out of which coherent rx buffer is allocated
273  * @tty_work: private work-queue for tty flip buffer push task
274  *
275  * This structure describes a single Rx DMA transaction. Rx DMA
276  * transactions use box mode DMA commands.
277  */
278 struct msm_hs_rx {
279 	enum flush_reason flush;
280 	struct msm_dmov_cmd xfer;
281 	dma_addr_t cmdptr_dmaaddr;
282 	dmov_box *command_ptr;
283 	u32 *command_ptr_ptr;
284 	dma_addr_t mapped_cmd_ptr;
285 	wait_queue_head_t wait;
286 	dma_addr_t rbuffer;
287 	unsigned char *buffer;
288 	struct dma_pool *pool;
289 	struct work_struct tty_work;
290 };
291 
292 /**
293  * struct msm_hs_rx_wakeup
294  * @irq: IRQ line to be configured as interrupt source on Rx activity
295  * @ignore: boolean value. 1 = ignore the wakeup interrupt
296  * @rx_to_inject: extra character to be inserted to Rx tty on wakeup
297  * @inject_rx: 1 = insert rx_to_inject. 0 = do not insert extra character
298  *
299  * This is an optional structure required for UART Rx GPIO IRQ based
300  * wakeup from low power state. UART wakeup can be triggered by RX activity
301  * (using a wakeup GPIO on the UART RX pin). This should only be used if
302  * there is not a wakeup GPIO on the UART CTS, and the first RX byte is
303  * known (eg., with the Bluetooth Texas Instruments HCILL protocol),
304  * since the first RX byte will always be lost. RTS will be asserted even
305  * while the UART is clocked off in this mode of operation.
306  */
307 struct msm_hs_rx_wakeup {
308 	int irq;  /* < 0 indicates low power wakeup disabled */
309 	unsigned char ignore;
310 	unsigned char inject_rx;
311 	char rx_to_inject;
312 };
313 
314 /**
315  * struct msm_hs_port
316  * @uport: embedded uart port structure
317  * @imr_reg: shadow value of UARTDM_IMR
318  * @clk: uart input clock handle
319  * @tx: Tx transaction related data structure
320  * @rx: Rx transaction related data structure
321  * @dma_tx_channel: Tx DMA command channel
322  * @dma_rx_channel Rx DMA command channel
323  * @dma_tx_crci: Tx channel rate control interface number
324  * @dma_rx_crci: Rx channel rate control interface number
325  * @clk_off_timer: Timer to poll DMA event completion before clock off
326  * @clk_off_delay: clk_off_timer poll interval
327  * @clk_state: overall clock state
328  * @clk_req_off_state: post flush clock states
329  * @rx_wakeup: optional rx_wakeup feature related data
330  * @exit_lpm_cb: optional callback to exit low power mode
331  *
332  * Low level serial port structure.
333  */
334 struct msm_hs_port {
335 	struct uart_port uport;
336 	unsigned long imr_reg;
337 	struct clk *clk;
338 	struct msm_hs_tx tx;
339 	struct msm_hs_rx rx;
340 
341 	int dma_tx_channel;
342 	int dma_rx_channel;
343 	int dma_tx_crci;
344 	int dma_rx_crci;
345 
346 	struct hrtimer clk_off_timer;
347 	ktime_t clk_off_delay;
348 	enum msm_hs_clk_states_e clk_state;
349 	enum msm_hs_clk_req_off_state_e clk_req_off_state;
350 
351 	struct msm_hs_rx_wakeup rx_wakeup;
352 	void (*exit_lpm_cb)(struct uart_port *);
353 };
354 
355 #define MSM_UARTDM_BURST_SIZE 16   /* DM burst size (in bytes) */
356 #define UARTDM_TX_BUF_SIZE UART_XMIT_SIZE
357 #define UARTDM_RX_BUF_SIZE 512
358 
359 #define UARTDM_NR 2
360 
361 static struct msm_hs_port q_uart_port[UARTDM_NR];
362 static struct platform_driver msm_serial_hs_platform_driver;
363 static struct uart_driver msm_hs_driver;
364 static struct uart_ops msm_hs_ops;
365 static struct workqueue_struct *msm_hs_workqueue;
366 
367 #define UARTDM_TO_MSM(uart_port) \
368 	container_of((uart_port), struct msm_hs_port, uport)
369 
use_low_power_rx_wakeup(struct msm_hs_port * msm_uport)370 static unsigned int use_low_power_rx_wakeup(struct msm_hs_port
371 						   *msm_uport)
372 {
373 	return (msm_uport->rx_wakeup.irq >= 0);
374 }
375 
msm_hs_read(struct uart_port * uport,unsigned int offset)376 static unsigned int msm_hs_read(struct uart_port *uport,
377 				       unsigned int offset)
378 {
379 	return ioread32(uport->membase + offset);
380 }
381 
msm_hs_write(struct uart_port * uport,unsigned int offset,unsigned int value)382 static void msm_hs_write(struct uart_port *uport, unsigned int offset,
383 				 unsigned int value)
384 {
385 	iowrite32(value, uport->membase + offset);
386 }
387 
msm_hs_release_port(struct uart_port * port)388 static void msm_hs_release_port(struct uart_port *port)
389 {
390 	iounmap(port->membase);
391 }
392 
msm_hs_request_port(struct uart_port * port)393 static int msm_hs_request_port(struct uart_port *port)
394 {
395 	port->membase = ioremap(port->mapbase, PAGE_SIZE);
396 	if (unlikely(!port->membase))
397 		return -ENOMEM;
398 
399 	/* configure the CR Protection to Enable */
400 	msm_hs_write(port, UARTDM_CR_ADDR, CR_PROTECTION_EN);
401 	return 0;
402 }
403 
msm_hs_remove(struct platform_device * pdev)404 static int __devexit msm_hs_remove(struct platform_device *pdev)
405 {
406 
407 	struct msm_hs_port *msm_uport;
408 	struct device *dev;
409 
410 	if (pdev->id < 0 || pdev->id >= UARTDM_NR) {
411 		printk(KERN_ERR "Invalid plaform device ID = %d\n", pdev->id);
412 		return -EINVAL;
413 	}
414 
415 	msm_uport = &q_uart_port[pdev->id];
416 	dev = msm_uport->uport.dev;
417 
418 	dma_unmap_single(dev, msm_uport->rx.mapped_cmd_ptr, sizeof(dmov_box),
419 			 DMA_TO_DEVICE);
420 	dma_pool_free(msm_uport->rx.pool, msm_uport->rx.buffer,
421 		      msm_uport->rx.rbuffer);
422 	dma_pool_destroy(msm_uport->rx.pool);
423 
424 	dma_unmap_single(dev, msm_uport->rx.cmdptr_dmaaddr, sizeof(u32),
425 			 DMA_TO_DEVICE);
426 	dma_unmap_single(dev, msm_uport->tx.mapped_cmd_ptr_ptr, sizeof(u32),
427 			 DMA_TO_DEVICE);
428 	dma_unmap_single(dev, msm_uport->tx.mapped_cmd_ptr, sizeof(dmov_box),
429 			 DMA_TO_DEVICE);
430 
431 	uart_remove_one_port(&msm_hs_driver, &msm_uport->uport);
432 	clk_put(msm_uport->clk);
433 
434 	/* Free the tx resources */
435 	kfree(msm_uport->tx.command_ptr);
436 	kfree(msm_uport->tx.command_ptr_ptr);
437 
438 	/* Free the rx resources */
439 	kfree(msm_uport->rx.command_ptr);
440 	kfree(msm_uport->rx.command_ptr_ptr);
441 
442 	iounmap(msm_uport->uport.membase);
443 
444 	return 0;
445 }
446 
msm_hs_init_clk_locked(struct uart_port * uport)447 static int msm_hs_init_clk_locked(struct uart_port *uport)
448 {
449 	int ret;
450 	struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport);
451 
452 	ret = clk_enable(msm_uport->clk);
453 	if (ret) {
454 		printk(KERN_ERR "Error could not turn on UART clk\n");
455 		return ret;
456 	}
457 
458 	/* Set up the MREG/NREG/DREG/MNDREG */
459 	ret = clk_set_rate(msm_uport->clk, uport->uartclk);
460 	if (ret) {
461 		printk(KERN_WARNING "Error setting clock rate on UART\n");
462 		clk_disable(msm_uport->clk);
463 		return ret;
464 	}
465 
466 	msm_uport->clk_state = MSM_HS_CLK_ON;
467 	return 0;
468 }
469 
470 /* Enable and Disable clocks  (Used for power management) */
msm_hs_pm(struct uart_port * uport,unsigned int state,unsigned int oldstate)471 static void msm_hs_pm(struct uart_port *uport, unsigned int state,
472 		      unsigned int oldstate)
473 {
474 	struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport);
475 
476 	if (use_low_power_rx_wakeup(msm_uport) ||
477 	    msm_uport->exit_lpm_cb)
478 		return;  /* ignore linux PM states,
479 			    use msm_hs_request_clock API */
480 
481 	switch (state) {
482 	case 0:
483 		clk_enable(msm_uport->clk);
484 		break;
485 	case 3:
486 		clk_disable(msm_uport->clk);
487 		break;
488 	default:
489 		dev_err(uport->dev, "msm_serial: Unknown PM state %d\n",
490 			state);
491 	}
492 }
493 
494 /*
495  * programs the UARTDM_CSR register with correct bit rates
496  *
497  * Interrupts should be disabled before we are called, as
498  * we modify Set Baud rate
499  * Set receive stale interrupt level, dependent on Bit Rate
500  * Goal is to have around 8 ms before indicate stale.
501  * roundup (((Bit Rate * .008) / 10) + 1
502  */
msm_hs_set_bps_locked(struct uart_port * uport,unsigned int bps)503 static void msm_hs_set_bps_locked(struct uart_port *uport,
504 				  unsigned int bps)
505 {
506 	unsigned long rxstale;
507 	unsigned long data;
508 	struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport);
509 
510 	switch (bps) {
511 	case 300:
512 		msm_hs_write(uport, UARTDM_CSR_ADDR, UARTDM_CSR_75);
513 		rxstale = 1;
514 		break;
515 	case 600:
516 		msm_hs_write(uport, UARTDM_CSR_ADDR, UARTDM_CSR_150);
517 		rxstale = 1;
518 		break;
519 	case 1200:
520 		msm_hs_write(uport, UARTDM_CSR_ADDR, UARTDM_CSR_300);
521 		rxstale = 1;
522 		break;
523 	case 2400:
524 		msm_hs_write(uport, UARTDM_CSR_ADDR, UARTDM_CSR_600);
525 		rxstale = 1;
526 		break;
527 	case 4800:
528 		msm_hs_write(uport, UARTDM_CSR_ADDR, UARTDM_CSR_1200);
529 		rxstale = 1;
530 		break;
531 	case 9600:
532 		msm_hs_write(uport, UARTDM_CSR_ADDR, UARTDM_CSR_2400);
533 		rxstale = 2;
534 		break;
535 	case 14400:
536 		msm_hs_write(uport, UARTDM_CSR_ADDR, UARTDM_CSR_3600);
537 		rxstale = 3;
538 		break;
539 	case 19200:
540 		msm_hs_write(uport, UARTDM_CSR_ADDR, UARTDM_CSR_4800);
541 		rxstale = 4;
542 		break;
543 	case 28800:
544 		msm_hs_write(uport, UARTDM_CSR_ADDR, UARTDM_CSR_7200);
545 		rxstale = 6;
546 		break;
547 	case 38400:
548 		msm_hs_write(uport, UARTDM_CSR_ADDR, UARTDM_CSR_9600);
549 		rxstale = 8;
550 		break;
551 	case 57600:
552 		msm_hs_write(uport, UARTDM_CSR_ADDR, UARTDM_CSR_14400);
553 		rxstale = 16;
554 		break;
555 	case 76800:
556 		msm_hs_write(uport, UARTDM_CSR_ADDR, UARTDM_CSR_19200);
557 		rxstale = 16;
558 		break;
559 	case 115200:
560 		msm_hs_write(uport, UARTDM_CSR_ADDR, UARTDM_CSR_28800);
561 		rxstale = 31;
562 		break;
563 	case 230400:
564 		msm_hs_write(uport, UARTDM_CSR_ADDR, UARTDM_CSR_57600);
565 		rxstale = 31;
566 		break;
567 	case 460800:
568 		msm_hs_write(uport, UARTDM_CSR_ADDR, UARTDM_CSR_115200);
569 		rxstale = 31;
570 		break;
571 	case 4000000:
572 	case 3686400:
573 	case 3200000:
574 	case 3500000:
575 	case 3000000:
576 	case 2500000:
577 	case 1500000:
578 	case 1152000:
579 	case 1000000:
580 	case 921600:
581 		msm_hs_write(uport, UARTDM_CSR_ADDR, UARTDM_CSR_115200);
582 		rxstale = 31;
583 		break;
584 	default:
585 		msm_hs_write(uport, UARTDM_CSR_ADDR, UARTDM_CSR_2400);
586 		/* default to 9600 */
587 		bps = 9600;
588 		rxstale = 2;
589 		break;
590 	}
591 	if (bps > 460800)
592 		uport->uartclk = bps * 16;
593 	else
594 		uport->uartclk = UARTCLK;
595 
596 	if (clk_set_rate(msm_uport->clk, uport->uartclk)) {
597 		printk(KERN_WARNING "Error setting clock rate on UART\n");
598 		return;
599 	}
600 
601 	data = rxstale & UARTDM_IPR_STALE_LSB_BMSK;
602 	data |= UARTDM_IPR_STALE_TIMEOUT_MSB_BMSK & (rxstale << 2);
603 
604 	msm_hs_write(uport, UARTDM_IPR_ADDR, data);
605 }
606 
607 /*
608  * termios :  new ktermios
609  * oldtermios:  old ktermios previous setting
610  *
611  * Configure the serial port
612  */
msm_hs_set_termios(struct uart_port * uport,struct ktermios * termios,struct ktermios * oldtermios)613 static void msm_hs_set_termios(struct uart_port *uport,
614 			       struct ktermios *termios,
615 			       struct ktermios *oldtermios)
616 {
617 	unsigned int bps;
618 	unsigned long data;
619 	unsigned long flags;
620 	unsigned int c_cflag = termios->c_cflag;
621 	struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport);
622 
623 	spin_lock_irqsave(&uport->lock, flags);
624 	clk_enable(msm_uport->clk);
625 
626 	/* 300 is the minimum baud support by the driver  */
627 	bps = uart_get_baud_rate(uport, termios, oldtermios, 200, 4000000);
628 
629 	/* Temporary remapping  200 BAUD to 3.2 mbps */
630 	if (bps == 200)
631 		bps = 3200000;
632 
633 	msm_hs_set_bps_locked(uport, bps);
634 
635 	data = msm_hs_read(uport, UARTDM_MR2_ADDR);
636 	data &= ~UARTDM_MR2_PARITY_MODE_BMSK;
637 	/* set parity */
638 	if (PARENB == (c_cflag & PARENB)) {
639 		if (PARODD == (c_cflag & PARODD))
640 			data |= ODD_PARITY;
641 		else if (CMSPAR == (c_cflag & CMSPAR))
642 			data |= SPACE_PARITY;
643 		else
644 			data |= EVEN_PARITY;
645 	}
646 
647 	/* Set bits per char */
648 	data &= ~UARTDM_MR2_BITS_PER_CHAR_BMSK;
649 
650 	switch (c_cflag & CSIZE) {
651 	case CS5:
652 		data |= FIVE_BPC;
653 		break;
654 	case CS6:
655 		data |= SIX_BPC;
656 		break;
657 	case CS7:
658 		data |= SEVEN_BPC;
659 		break;
660 	default:
661 		data |= EIGHT_BPC;
662 		break;
663 	}
664 	/* stop bits */
665 	if (c_cflag & CSTOPB) {
666 		data |= STOP_BIT_TWO;
667 	} else {
668 		/* otherwise 1 stop bit */
669 		data |= STOP_BIT_ONE;
670 	}
671 	data |= UARTDM_MR2_ERROR_MODE_BMSK;
672 	/* write parity/bits per char/stop bit configuration */
673 	msm_hs_write(uport, UARTDM_MR2_ADDR, data);
674 
675 	/* Configure HW flow control */
676 	data = msm_hs_read(uport, UARTDM_MR1_ADDR);
677 
678 	data &= ~(UARTDM_MR1_CTS_CTL_BMSK | UARTDM_MR1_RX_RDY_CTL_BMSK);
679 
680 	if (c_cflag & CRTSCTS) {
681 		data |= UARTDM_MR1_CTS_CTL_BMSK;
682 		data |= UARTDM_MR1_RX_RDY_CTL_BMSK;
683 	}
684 
685 	msm_hs_write(uport, UARTDM_MR1_ADDR, data);
686 
687 	uport->ignore_status_mask = termios->c_iflag & INPCK;
688 	uport->ignore_status_mask |= termios->c_iflag & IGNPAR;
689 	uport->read_status_mask = (termios->c_cflag & CREAD);
690 
691 	msm_hs_write(uport, UARTDM_IMR_ADDR, 0);
692 
693 	/* Set Transmit software time out */
694 	uart_update_timeout(uport, c_cflag, bps);
695 
696 	msm_hs_write(uport, UARTDM_CR_ADDR, RESET_RX);
697 	msm_hs_write(uport, UARTDM_CR_ADDR, RESET_TX);
698 
699 	if (msm_uport->rx.flush == FLUSH_NONE) {
700 		msm_uport->rx.flush = FLUSH_IGNORE;
701 		msm_dmov_stop_cmd(msm_uport->dma_rx_channel, NULL, 1);
702 	}
703 
704 	msm_hs_write(uport, UARTDM_IMR_ADDR, msm_uport->imr_reg);
705 
706 	clk_disable(msm_uport->clk);
707 	spin_unlock_irqrestore(&uport->lock, flags);
708 }
709 
710 /*
711  *  Standard API, Transmitter
712  *  Any character in the transmit shift register is sent
713  */
msm_hs_tx_empty(struct uart_port * uport)714 static unsigned int msm_hs_tx_empty(struct uart_port *uport)
715 {
716 	unsigned int data;
717 	unsigned int ret = 0;
718 	struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport);
719 
720 	clk_enable(msm_uport->clk);
721 
722 	data = msm_hs_read(uport, UARTDM_SR_ADDR);
723 	if (data & UARTDM_SR_TXEMT_BMSK)
724 		ret = TIOCSER_TEMT;
725 
726 	clk_disable(msm_uport->clk);
727 
728 	return ret;
729 }
730 
731 /*
732  *  Standard API, Stop transmitter.
733  *  Any character in the transmit shift register is sent as
734  *  well as the current data mover transfer .
735  */
msm_hs_stop_tx_locked(struct uart_port * uport)736 static void msm_hs_stop_tx_locked(struct uart_port *uport)
737 {
738 	struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport);
739 
740 	msm_uport->tx.tx_ready_int_en = 0;
741 }
742 
743 /*
744  *  Standard API, Stop receiver as soon as possible.
745  *
746  *  Function immediately terminates the operation of the
747  *  channel receiver and any incoming characters are lost. None
748  *  of the receiver status bits are affected by this command and
749  *  characters that are already in the receive FIFO there.
750  */
msm_hs_stop_rx_locked(struct uart_port * uport)751 static void msm_hs_stop_rx_locked(struct uart_port *uport)
752 {
753 	struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport);
754 	unsigned int data;
755 
756 	clk_enable(msm_uport->clk);
757 
758 	/* disable dlink */
759 	data = msm_hs_read(uport, UARTDM_DMEN_ADDR);
760 	data &= ~UARTDM_RX_DM_EN_BMSK;
761 	msm_hs_write(uport, UARTDM_DMEN_ADDR, data);
762 
763 	/* Disable the receiver */
764 	if (msm_uport->rx.flush == FLUSH_NONE)
765 		msm_dmov_stop_cmd(msm_uport->dma_rx_channel, NULL, 1);
766 
767 	if (msm_uport->rx.flush != FLUSH_SHUTDOWN)
768 		msm_uport->rx.flush = FLUSH_STOP;
769 
770 	clk_disable(msm_uport->clk);
771 }
772 
773 /*  Transmit the next chunk of data */
msm_hs_submit_tx_locked(struct uart_port * uport)774 static void msm_hs_submit_tx_locked(struct uart_port *uport)
775 {
776 	int left;
777 	int tx_count;
778 	dma_addr_t src_addr;
779 	struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport);
780 	struct msm_hs_tx *tx = &msm_uport->tx;
781 	struct circ_buf *tx_buf = &msm_uport->uport.state->xmit;
782 
783 	if (uart_circ_empty(tx_buf) || uport->state->port.tty->stopped) {
784 		msm_hs_stop_tx_locked(uport);
785 		return;
786 	}
787 
788 	tx->dma_in_flight = 1;
789 
790 	tx_count = uart_circ_chars_pending(tx_buf);
791 
792 	if (UARTDM_TX_BUF_SIZE < tx_count)
793 		tx_count = UARTDM_TX_BUF_SIZE;
794 
795 	left = UART_XMIT_SIZE - tx_buf->tail;
796 
797 	if (tx_count > left)
798 		tx_count = left;
799 
800 	src_addr = tx->dma_base + tx_buf->tail;
801 	dma_sync_single_for_device(uport->dev, src_addr, tx_count,
802 				   DMA_TO_DEVICE);
803 
804 	tx->command_ptr->num_rows = (((tx_count + 15) >> 4) << 16) |
805 				     ((tx_count + 15) >> 4);
806 	tx->command_ptr->src_row_addr = src_addr;
807 
808 	dma_sync_single_for_device(uport->dev, tx->mapped_cmd_ptr,
809 				   sizeof(dmov_box), DMA_TO_DEVICE);
810 
811 	*tx->command_ptr_ptr = CMD_PTR_LP | DMOV_CMD_ADDR(tx->mapped_cmd_ptr);
812 
813 	dma_sync_single_for_device(uport->dev, tx->mapped_cmd_ptr_ptr,
814 				   sizeof(u32), DMA_TO_DEVICE);
815 
816 	/* Save tx_count to use in Callback */
817 	tx->tx_count = tx_count;
818 	msm_hs_write(uport, UARTDM_NCF_TX_ADDR, tx_count);
819 
820 	/* Disable the tx_ready interrupt */
821 	msm_uport->imr_reg &= ~UARTDM_ISR_TX_READY_BMSK;
822 	msm_hs_write(uport, UARTDM_IMR_ADDR, msm_uport->imr_reg);
823 	msm_dmov_enqueue_cmd(msm_uport->dma_tx_channel, &tx->xfer);
824 }
825 
826 /* Start to receive the next chunk of data */
msm_hs_start_rx_locked(struct uart_port * uport)827 static void msm_hs_start_rx_locked(struct uart_port *uport)
828 {
829 	struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport);
830 
831 	msm_hs_write(uport, UARTDM_CR_ADDR, RESET_STALE_INT);
832 	msm_hs_write(uport, UARTDM_DMRX_ADDR, UARTDM_RX_BUF_SIZE);
833 	msm_hs_write(uport, UARTDM_CR_ADDR, STALE_EVENT_ENABLE);
834 	msm_uport->imr_reg |= UARTDM_ISR_RXLEV_BMSK;
835 	msm_hs_write(uport, UARTDM_IMR_ADDR, msm_uport->imr_reg);
836 
837 	msm_uport->rx.flush = FLUSH_NONE;
838 	msm_dmov_enqueue_cmd(msm_uport->dma_rx_channel, &msm_uport->rx.xfer);
839 
840 	/* might have finished RX and be ready to clock off */
841 	hrtimer_start(&msm_uport->clk_off_timer, msm_uport->clk_off_delay,
842 			HRTIMER_MODE_REL);
843 }
844 
845 /* Enable the transmitter Interrupt */
msm_hs_start_tx_locked(struct uart_port * uport)846 static void msm_hs_start_tx_locked(struct uart_port *uport)
847 {
848 	struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport);
849 
850 	clk_enable(msm_uport->clk);
851 
852 	if (msm_uport->exit_lpm_cb)
853 		msm_uport->exit_lpm_cb(uport);
854 
855 	if (msm_uport->tx.tx_ready_int_en == 0) {
856 		msm_uport->tx.tx_ready_int_en = 1;
857 		msm_hs_submit_tx_locked(uport);
858 	}
859 
860 	clk_disable(msm_uport->clk);
861 }
862 
863 /*
864  *  This routine is called when we are done with a DMA transfer
865  *
866  *  This routine is registered with Data mover when we set
867  *  up a Data Mover transfer. It is called from Data mover ISR
868  *  when the DMA transfer is done.
869  */
msm_hs_dmov_tx_callback(struct msm_dmov_cmd * cmd_ptr,unsigned int result,struct msm_dmov_errdata * err)870 static void msm_hs_dmov_tx_callback(struct msm_dmov_cmd *cmd_ptr,
871 					unsigned int result,
872 					struct msm_dmov_errdata *err)
873 {
874 	unsigned long flags;
875 	struct msm_hs_port *msm_uport;
876 
877 	/* DMA did not finish properly */
878 	WARN_ON((((result & RSLT_FIFO_CNTR_BMSK) >> 28) == 1) &&
879 		!(result & RSLT_VLD));
880 
881 	msm_uport = container_of(cmd_ptr, struct msm_hs_port, tx.xfer);
882 
883 	spin_lock_irqsave(&msm_uport->uport.lock, flags);
884 	clk_enable(msm_uport->clk);
885 
886 	msm_uport->imr_reg |= UARTDM_ISR_TX_READY_BMSK;
887 	msm_hs_write(&msm_uport->uport, UARTDM_IMR_ADDR, msm_uport->imr_reg);
888 
889 	clk_disable(msm_uport->clk);
890 	spin_unlock_irqrestore(&msm_uport->uport.lock, flags);
891 }
892 
893 /*
894  * This routine is called when we are done with a DMA transfer or the
895  * a flush has been sent to the data mover driver.
896  *
897  * This routine is registered with Data mover when we set up a Data Mover
898  *  transfer. It is called from Data mover ISR when the DMA transfer is done.
899  */
msm_hs_dmov_rx_callback(struct msm_dmov_cmd * cmd_ptr,unsigned int result,struct msm_dmov_errdata * err)900 static void msm_hs_dmov_rx_callback(struct msm_dmov_cmd *cmd_ptr,
901 					unsigned int result,
902 					struct msm_dmov_errdata *err)
903 {
904 	int retval;
905 	int rx_count;
906 	unsigned long status;
907 	unsigned int error_f = 0;
908 	unsigned long flags;
909 	unsigned int flush;
910 	struct tty_struct *tty;
911 	struct uart_port *uport;
912 	struct msm_hs_port *msm_uport;
913 
914 	msm_uport = container_of(cmd_ptr, struct msm_hs_port, rx.xfer);
915 	uport = &msm_uport->uport;
916 
917 	spin_lock_irqsave(&uport->lock, flags);
918 	clk_enable(msm_uport->clk);
919 
920 	tty = uport->state->port.tty;
921 
922 	msm_hs_write(uport, UARTDM_CR_ADDR, STALE_EVENT_DISABLE);
923 
924 	status = msm_hs_read(uport, UARTDM_SR_ADDR);
925 
926 	/* overflow is not connect to data in a FIFO */
927 	if (unlikely((status & UARTDM_SR_OVERRUN_BMSK) &&
928 		     (uport->read_status_mask & CREAD))) {
929 		tty_insert_flip_char(tty, 0, TTY_OVERRUN);
930 		uport->icount.buf_overrun++;
931 		error_f = 1;
932 	}
933 
934 	if (!(uport->ignore_status_mask & INPCK))
935 		status = status & ~(UARTDM_SR_PAR_FRAME_BMSK);
936 
937 	if (unlikely(status & UARTDM_SR_PAR_FRAME_BMSK)) {
938 		/* Can not tell difference between parity & frame error */
939 		uport->icount.parity++;
940 		error_f = 1;
941 		if (uport->ignore_status_mask & IGNPAR)
942 			tty_insert_flip_char(tty, 0, TTY_PARITY);
943 	}
944 
945 	if (error_f)
946 		msm_hs_write(uport, UARTDM_CR_ADDR, RESET_ERROR_STATUS);
947 
948 	if (msm_uport->clk_req_off_state == CLK_REQ_OFF_FLUSH_ISSUED)
949 		msm_uport->clk_req_off_state = CLK_REQ_OFF_RXSTALE_FLUSHED;
950 
951 	flush = msm_uport->rx.flush;
952 	if (flush == FLUSH_IGNORE)
953 		msm_hs_start_rx_locked(uport);
954 	if (flush == FLUSH_STOP)
955 		msm_uport->rx.flush = FLUSH_SHUTDOWN;
956 	if (flush >= FLUSH_DATA_INVALID)
957 		goto out;
958 
959 	rx_count = msm_hs_read(uport, UARTDM_RX_TOTAL_SNAP_ADDR);
960 
961 	if (0 != (uport->read_status_mask & CREAD)) {
962 		retval = tty_insert_flip_string(tty, msm_uport->rx.buffer,
963 						rx_count);
964 		BUG_ON(retval != rx_count);
965 	}
966 
967 	msm_hs_start_rx_locked(uport);
968 
969 out:
970 	clk_disable(msm_uport->clk);
971 
972 	spin_unlock_irqrestore(&uport->lock, flags);
973 
974 	if (flush < FLUSH_DATA_INVALID)
975 		queue_work(msm_hs_workqueue, &msm_uport->rx.tty_work);
976 }
977 
msm_hs_tty_flip_buffer_work(struct work_struct * work)978 static void msm_hs_tty_flip_buffer_work(struct work_struct *work)
979 {
980 	struct msm_hs_port *msm_uport =
981 			container_of(work, struct msm_hs_port, rx.tty_work);
982 	struct tty_struct *tty = msm_uport->uport.state->port.tty;
983 
984 	tty_flip_buffer_push(tty);
985 }
986 
987 /*
988  *  Standard API, Current states of modem control inputs
989  *
990  * Since CTS can be handled entirely by HARDWARE we always
991  * indicate clear to send and count on the TX FIFO to block when
992  * it fills up.
993  *
994  * - TIOCM_DCD
995  * - TIOCM_CTS
996  * - TIOCM_DSR
997  * - TIOCM_RI
998  *  (Unsupported) DCD and DSR will return them high. RI will return low.
999  */
msm_hs_get_mctrl_locked(struct uart_port * uport)1000 static unsigned int msm_hs_get_mctrl_locked(struct uart_port *uport)
1001 {
1002 	return TIOCM_DSR | TIOCM_CAR | TIOCM_CTS;
1003 }
1004 
1005 /*
1006  * True enables UART auto RFR, which indicates we are ready for data if the RX
1007  * buffer is not full. False disables auto RFR, and deasserts RFR to indicate
1008  * we are not ready for data. Must be called with UART clock on.
1009  */
set_rfr_locked(struct uart_port * uport,int auto_rfr)1010 static void set_rfr_locked(struct uart_port *uport, int auto_rfr)
1011 {
1012 	unsigned int data;
1013 
1014 	data = msm_hs_read(uport, UARTDM_MR1_ADDR);
1015 
1016 	if (auto_rfr) {
1017 		/* enable auto ready-for-receiving */
1018 		data |= UARTDM_MR1_RX_RDY_CTL_BMSK;
1019 		msm_hs_write(uport, UARTDM_MR1_ADDR, data);
1020 	} else {
1021 		/* disable auto ready-for-receiving */
1022 		data &= ~UARTDM_MR1_RX_RDY_CTL_BMSK;
1023 		msm_hs_write(uport, UARTDM_MR1_ADDR, data);
1024 		/* RFR is active low, set high */
1025 		msm_hs_write(uport, UARTDM_CR_ADDR, RFR_HIGH);
1026 	}
1027 }
1028 
1029 /*
1030  *  Standard API, used to set or clear RFR
1031  */
msm_hs_set_mctrl_locked(struct uart_port * uport,unsigned int mctrl)1032 static void msm_hs_set_mctrl_locked(struct uart_port *uport,
1033 				    unsigned int mctrl)
1034 {
1035 	unsigned int auto_rfr;
1036 	struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport);
1037 
1038 	clk_enable(msm_uport->clk);
1039 
1040 	auto_rfr = TIOCM_RTS & mctrl ? 1 : 0;
1041 	set_rfr_locked(uport, auto_rfr);
1042 
1043 	clk_disable(msm_uport->clk);
1044 }
1045 
1046 /* Standard API, Enable modem status (CTS) interrupt  */
msm_hs_enable_ms_locked(struct uart_port * uport)1047 static void msm_hs_enable_ms_locked(struct uart_port *uport)
1048 {
1049 	struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport);
1050 
1051 	clk_enable(msm_uport->clk);
1052 
1053 	/* Enable DELTA_CTS Interrupt */
1054 	msm_uport->imr_reg |= UARTDM_ISR_DELTA_CTS_BMSK;
1055 	msm_hs_write(uport, UARTDM_IMR_ADDR, msm_uport->imr_reg);
1056 
1057 	clk_disable(msm_uport->clk);
1058 
1059 }
1060 
1061 /*
1062  *  Standard API, Break Signal
1063  *
1064  * Control the transmission of a break signal. ctl eq 0 => break
1065  * signal terminate ctl ne 0 => start break signal
1066  */
msm_hs_break_ctl(struct uart_port * uport,int ctl)1067 static void msm_hs_break_ctl(struct uart_port *uport, int ctl)
1068 {
1069 	struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport);
1070 
1071 	clk_enable(msm_uport->clk);
1072 	msm_hs_write(uport, UARTDM_CR_ADDR, ctl ? START_BREAK : STOP_BREAK);
1073 	clk_disable(msm_uport->clk);
1074 }
1075 
msm_hs_config_port(struct uart_port * uport,int cfg_flags)1076 static void msm_hs_config_port(struct uart_port *uport, int cfg_flags)
1077 {
1078 	unsigned long flags;
1079 
1080 	spin_lock_irqsave(&uport->lock, flags);
1081 	if (cfg_flags & UART_CONFIG_TYPE) {
1082 		uport->type = PORT_MSM;
1083 		msm_hs_request_port(uport);
1084 	}
1085 	spin_unlock_irqrestore(&uport->lock, flags);
1086 }
1087 
1088 /*  Handle CTS changes (Called from interrupt handler) */
msm_hs_handle_delta_cts_locked(struct uart_port * uport)1089 static void msm_hs_handle_delta_cts_locked(struct uart_port *uport)
1090 {
1091 	struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport);
1092 
1093 	clk_enable(msm_uport->clk);
1094 
1095 	/* clear interrupt */
1096 	msm_hs_write(uport, UARTDM_CR_ADDR, RESET_CTS);
1097 	uport->icount.cts++;
1098 
1099 	clk_disable(msm_uport->clk);
1100 
1101 	/* clear the IOCTL TIOCMIWAIT if called */
1102 	wake_up_interruptible(&uport->state->port.delta_msr_wait);
1103 }
1104 
1105 /* check if the TX path is flushed, and if so clock off
1106  * returns 0 did not clock off, need to retry (still sending final byte)
1107  *        -1 did not clock off, do not retry
1108  *         1 if we clocked off
1109  */
msm_hs_check_clock_off_locked(struct uart_port * uport)1110 static int msm_hs_check_clock_off_locked(struct uart_port *uport)
1111 {
1112 	unsigned long sr_status;
1113 	struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport);
1114 	struct circ_buf *tx_buf = &uport->state->xmit;
1115 
1116 	/* Cancel if tx tty buffer is not empty, dma is in flight,
1117 	 * or tx fifo is not empty, or rx fifo is not empty */
1118 	if (msm_uport->clk_state != MSM_HS_CLK_REQUEST_OFF ||
1119 	    !uart_circ_empty(tx_buf) || msm_uport->tx.dma_in_flight ||
1120 	    (msm_uport->imr_reg & UARTDM_ISR_TXLEV_BMSK) ||
1121 	    !(msm_uport->imr_reg & UARTDM_ISR_RXLEV_BMSK))  {
1122 		return -1;
1123 	}
1124 
1125 	/* Make sure the uart is finished with the last byte */
1126 	sr_status = msm_hs_read(uport, UARTDM_SR_ADDR);
1127 	if (!(sr_status & UARTDM_SR_TXEMT_BMSK))
1128 		return 0;  /* retry */
1129 
1130 	/* Make sure forced RXSTALE flush complete */
1131 	switch (msm_uport->clk_req_off_state) {
1132 	case CLK_REQ_OFF_START:
1133 		msm_uport->clk_req_off_state = CLK_REQ_OFF_RXSTALE_ISSUED;
1134 		msm_hs_write(uport, UARTDM_CR_ADDR, FORCE_STALE_EVENT);
1135 		return 0;  /* RXSTALE flush not complete - retry */
1136 	case CLK_REQ_OFF_RXSTALE_ISSUED:
1137 	case CLK_REQ_OFF_FLUSH_ISSUED:
1138 		return 0;  /* RXSTALE flush not complete - retry */
1139 	case CLK_REQ_OFF_RXSTALE_FLUSHED:
1140 		break;  /* continue */
1141 	}
1142 
1143 	if (msm_uport->rx.flush != FLUSH_SHUTDOWN) {
1144 		if (msm_uport->rx.flush == FLUSH_NONE)
1145 			msm_hs_stop_rx_locked(uport);
1146 		return 0;  /* come back later to really clock off */
1147 	}
1148 
1149 	/* we really want to clock off */
1150 	clk_disable(msm_uport->clk);
1151 	msm_uport->clk_state = MSM_HS_CLK_OFF;
1152 
1153 	if (use_low_power_rx_wakeup(msm_uport)) {
1154 		msm_uport->rx_wakeup.ignore = 1;
1155 		enable_irq(msm_uport->rx_wakeup.irq);
1156 	}
1157 	return 1;
1158 }
1159 
msm_hs_clk_off_retry(struct hrtimer * timer)1160 static enum hrtimer_restart msm_hs_clk_off_retry(struct hrtimer *timer)
1161 {
1162 	unsigned long flags;
1163 	int ret = HRTIMER_NORESTART;
1164 	struct msm_hs_port *msm_uport = container_of(timer, struct msm_hs_port,
1165 						     clk_off_timer);
1166 	struct uart_port *uport = &msm_uport->uport;
1167 
1168 	spin_lock_irqsave(&uport->lock, flags);
1169 
1170 	if (!msm_hs_check_clock_off_locked(uport)) {
1171 		hrtimer_forward_now(timer, msm_uport->clk_off_delay);
1172 		ret = HRTIMER_RESTART;
1173 	}
1174 
1175 	spin_unlock_irqrestore(&uport->lock, flags);
1176 
1177 	return ret;
1178 }
1179 
msm_hs_isr(int irq,void * dev)1180 static irqreturn_t msm_hs_isr(int irq, void *dev)
1181 {
1182 	unsigned long flags;
1183 	unsigned long isr_status;
1184 	struct msm_hs_port *msm_uport = dev;
1185 	struct uart_port *uport = &msm_uport->uport;
1186 	struct circ_buf *tx_buf = &uport->state->xmit;
1187 	struct msm_hs_tx *tx = &msm_uport->tx;
1188 	struct msm_hs_rx *rx = &msm_uport->rx;
1189 
1190 	spin_lock_irqsave(&uport->lock, flags);
1191 
1192 	isr_status = msm_hs_read(uport, UARTDM_MISR_ADDR);
1193 
1194 	/* Uart RX starting */
1195 	if (isr_status & UARTDM_ISR_RXLEV_BMSK) {
1196 		msm_uport->imr_reg &= ~UARTDM_ISR_RXLEV_BMSK;
1197 		msm_hs_write(uport, UARTDM_IMR_ADDR, msm_uport->imr_reg);
1198 	}
1199 	/* Stale rx interrupt */
1200 	if (isr_status & UARTDM_ISR_RXSTALE_BMSK) {
1201 		msm_hs_write(uport, UARTDM_CR_ADDR, STALE_EVENT_DISABLE);
1202 		msm_hs_write(uport, UARTDM_CR_ADDR, RESET_STALE_INT);
1203 
1204 		if (msm_uport->clk_req_off_state == CLK_REQ_OFF_RXSTALE_ISSUED)
1205 			msm_uport->clk_req_off_state =
1206 					CLK_REQ_OFF_FLUSH_ISSUED;
1207 		if (rx->flush == FLUSH_NONE) {
1208 			rx->flush = FLUSH_DATA_READY;
1209 			msm_dmov_stop_cmd(msm_uport->dma_rx_channel, NULL, 1);
1210 		}
1211 	}
1212 	/* tx ready interrupt */
1213 	if (isr_status & UARTDM_ISR_TX_READY_BMSK) {
1214 		/* Clear  TX Ready */
1215 		msm_hs_write(uport, UARTDM_CR_ADDR, CLEAR_TX_READY);
1216 
1217 		if (msm_uport->clk_state == MSM_HS_CLK_REQUEST_OFF) {
1218 			msm_uport->imr_reg |= UARTDM_ISR_TXLEV_BMSK;
1219 			msm_hs_write(uport, UARTDM_IMR_ADDR,
1220 				     msm_uport->imr_reg);
1221 		}
1222 
1223 		/* Complete DMA TX transactions and submit new transactions */
1224 		tx_buf->tail = (tx_buf->tail + tx->tx_count) & ~UART_XMIT_SIZE;
1225 
1226 		tx->dma_in_flight = 0;
1227 
1228 		uport->icount.tx += tx->tx_count;
1229 		if (tx->tx_ready_int_en)
1230 			msm_hs_submit_tx_locked(uport);
1231 
1232 		if (uart_circ_chars_pending(tx_buf) < WAKEUP_CHARS)
1233 			uart_write_wakeup(uport);
1234 	}
1235 	if (isr_status & UARTDM_ISR_TXLEV_BMSK) {
1236 		/* TX FIFO is empty */
1237 		msm_uport->imr_reg &= ~UARTDM_ISR_TXLEV_BMSK;
1238 		msm_hs_write(uport, UARTDM_IMR_ADDR, msm_uport->imr_reg);
1239 		if (!msm_hs_check_clock_off_locked(uport))
1240 			hrtimer_start(&msm_uport->clk_off_timer,
1241 				      msm_uport->clk_off_delay,
1242 				      HRTIMER_MODE_REL);
1243 	}
1244 
1245 	/* Change in CTS interrupt */
1246 	if (isr_status & UARTDM_ISR_DELTA_CTS_BMSK)
1247 		msm_hs_handle_delta_cts_locked(uport);
1248 
1249 	spin_unlock_irqrestore(&uport->lock, flags);
1250 
1251 	return IRQ_HANDLED;
1252 }
1253 
msm_hs_request_clock_off_locked(struct uart_port * uport)1254 void msm_hs_request_clock_off_locked(struct uart_port *uport)
1255 {
1256 	struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport);
1257 
1258 	if (msm_uport->clk_state == MSM_HS_CLK_ON) {
1259 		msm_uport->clk_state = MSM_HS_CLK_REQUEST_OFF;
1260 		msm_uport->clk_req_off_state = CLK_REQ_OFF_START;
1261 		if (!use_low_power_rx_wakeup(msm_uport))
1262 			set_rfr_locked(uport, 0);
1263 		msm_uport->imr_reg |= UARTDM_ISR_TXLEV_BMSK;
1264 		msm_hs_write(uport, UARTDM_IMR_ADDR, msm_uport->imr_reg);
1265 	}
1266 }
1267 
1268 /**
1269  * msm_hs_request_clock_off - request to (i.e. asynchronously) turn off uart
1270  * clock once pending TX is flushed and Rx DMA command is terminated.
1271  * @uport: uart_port structure for the device instance.
1272  *
1273  * This functions puts the device into a partially active low power mode. It
1274  * waits to complete all pending tx transactions, flushes ongoing Rx DMA
1275  * command and terminates UART side Rx transaction, puts UART HW in non DMA
1276  * mode and then clocks off the device. A client calls this when no UART
1277  * data is expected. msm_request_clock_on() must be called before any further
1278  * UART can be sent or received.
1279  */
msm_hs_request_clock_off(struct uart_port * uport)1280 void msm_hs_request_clock_off(struct uart_port *uport)
1281 {
1282 	unsigned long flags;
1283 
1284 	spin_lock_irqsave(&uport->lock, flags);
1285 	msm_hs_request_clock_off_locked(uport);
1286 	spin_unlock_irqrestore(&uport->lock, flags);
1287 }
1288 
msm_hs_request_clock_on_locked(struct uart_port * uport)1289 void msm_hs_request_clock_on_locked(struct uart_port *uport)
1290 {
1291 	struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport);
1292 	unsigned int data;
1293 
1294 	switch (msm_uport->clk_state) {
1295 	case MSM_HS_CLK_OFF:
1296 		clk_enable(msm_uport->clk);
1297 		disable_irq_nosync(msm_uport->rx_wakeup.irq);
1298 		/* fall-through */
1299 	case MSM_HS_CLK_REQUEST_OFF:
1300 		if (msm_uport->rx.flush == FLUSH_STOP ||
1301 		    msm_uport->rx.flush == FLUSH_SHUTDOWN) {
1302 			msm_hs_write(uport, UARTDM_CR_ADDR, RESET_RX);
1303 			data = msm_hs_read(uport, UARTDM_DMEN_ADDR);
1304 			data |= UARTDM_RX_DM_EN_BMSK;
1305 			msm_hs_write(uport, UARTDM_DMEN_ADDR, data);
1306 		}
1307 		hrtimer_try_to_cancel(&msm_uport->clk_off_timer);
1308 		if (msm_uport->rx.flush == FLUSH_SHUTDOWN)
1309 			msm_hs_start_rx_locked(uport);
1310 		if (!use_low_power_rx_wakeup(msm_uport))
1311 			set_rfr_locked(uport, 1);
1312 		if (msm_uport->rx.flush == FLUSH_STOP)
1313 			msm_uport->rx.flush = FLUSH_IGNORE;
1314 		msm_uport->clk_state = MSM_HS_CLK_ON;
1315 		break;
1316 	case MSM_HS_CLK_ON:
1317 		break;
1318 	case MSM_HS_CLK_PORT_OFF:
1319 		break;
1320 	}
1321 }
1322 
1323 /**
1324  * msm_hs_request_clock_on - Switch the device from partially active low
1325  * power mode to fully active (i.e. clock on) mode.
1326  * @uport: uart_port structure for the device.
1327  *
1328  * This function switches on the input clock, puts UART HW into DMA mode
1329  * and enqueues an Rx DMA command if the device was in partially active
1330  * mode. It has no effect if called with the device in inactive state.
1331  */
msm_hs_request_clock_on(struct uart_port * uport)1332 void msm_hs_request_clock_on(struct uart_port *uport)
1333 {
1334 	unsigned long flags;
1335 
1336 	spin_lock_irqsave(&uport->lock, flags);
1337 	msm_hs_request_clock_on_locked(uport);
1338 	spin_unlock_irqrestore(&uport->lock, flags);
1339 }
1340 
msm_hs_rx_wakeup_isr(int irq,void * dev)1341 static irqreturn_t msm_hs_rx_wakeup_isr(int irq, void *dev)
1342 {
1343 	unsigned int wakeup = 0;
1344 	unsigned long flags;
1345 	struct msm_hs_port *msm_uport = dev;
1346 	struct uart_port *uport = &msm_uport->uport;
1347 	struct tty_struct *tty = NULL;
1348 
1349 	spin_lock_irqsave(&uport->lock, flags);
1350 	if (msm_uport->clk_state == MSM_HS_CLK_OFF) {
1351 		/* ignore the first irq - it is a pending irq that occurred
1352 		 * before enable_irq() */
1353 		if (msm_uport->rx_wakeup.ignore)
1354 			msm_uport->rx_wakeup.ignore = 0;
1355 		else
1356 			wakeup = 1;
1357 	}
1358 
1359 	if (wakeup) {
1360 		/* the uart was clocked off during an rx, wake up and
1361 		 * optionally inject char into tty rx */
1362 		msm_hs_request_clock_on_locked(uport);
1363 		if (msm_uport->rx_wakeup.inject_rx) {
1364 			tty = uport->state->port.tty;
1365 			tty_insert_flip_char(tty,
1366 					     msm_uport->rx_wakeup.rx_to_inject,
1367 					     TTY_NORMAL);
1368 			queue_work(msm_hs_workqueue, &msm_uport->rx.tty_work);
1369 		}
1370 	}
1371 
1372 	spin_unlock_irqrestore(&uport->lock, flags);
1373 
1374 	return IRQ_HANDLED;
1375 }
1376 
msm_hs_type(struct uart_port * port)1377 static const char *msm_hs_type(struct uart_port *port)
1378 {
1379 	return (port->type == PORT_MSM) ? "MSM_HS_UART" : NULL;
1380 }
1381 
1382 /* Called when port is opened */
msm_hs_startup(struct uart_port * uport)1383 static int msm_hs_startup(struct uart_port *uport)
1384 {
1385 	int ret;
1386 	int rfr_level;
1387 	unsigned long flags;
1388 	unsigned int data;
1389 	struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport);
1390 	struct circ_buf *tx_buf = &uport->state->xmit;
1391 	struct msm_hs_tx *tx = &msm_uport->tx;
1392 	struct msm_hs_rx *rx = &msm_uport->rx;
1393 
1394 	rfr_level = uport->fifosize;
1395 	if (rfr_level > 16)
1396 		rfr_level -= 16;
1397 
1398 	tx->dma_base = dma_map_single(uport->dev, tx_buf->buf, UART_XMIT_SIZE,
1399 				      DMA_TO_DEVICE);
1400 
1401 	/* do not let tty layer execute RX in global workqueue, use a
1402 	 * dedicated workqueue managed by this driver */
1403 	uport->state->port.tty->low_latency = 1;
1404 
1405 	/* turn on uart clk */
1406 	ret = msm_hs_init_clk_locked(uport);
1407 	if (unlikely(ret)) {
1408 		printk(KERN_ERR "Turning uartclk failed!\n");
1409 		goto err_msm_hs_init_clk;
1410 	}
1411 
1412 	/* Set auto RFR Level */
1413 	data = msm_hs_read(uport, UARTDM_MR1_ADDR);
1414 	data &= ~UARTDM_MR1_AUTO_RFR_LEVEL1_BMSK;
1415 	data &= ~UARTDM_MR1_AUTO_RFR_LEVEL0_BMSK;
1416 	data |= (UARTDM_MR1_AUTO_RFR_LEVEL1_BMSK & (rfr_level << 2));
1417 	data |= (UARTDM_MR1_AUTO_RFR_LEVEL0_BMSK & rfr_level);
1418 	msm_hs_write(uport, UARTDM_MR1_ADDR, data);
1419 
1420 	/* Make sure RXSTALE count is non-zero */
1421 	data = msm_hs_read(uport, UARTDM_IPR_ADDR);
1422 	if (!data) {
1423 		data |= 0x1f & UARTDM_IPR_STALE_LSB_BMSK;
1424 		msm_hs_write(uport, UARTDM_IPR_ADDR, data);
1425 	}
1426 
1427 	/* Enable Data Mover Mode */
1428 	data = UARTDM_TX_DM_EN_BMSK | UARTDM_RX_DM_EN_BMSK;
1429 	msm_hs_write(uport, UARTDM_DMEN_ADDR, data);
1430 
1431 	/* Reset TX */
1432 	msm_hs_write(uport, UARTDM_CR_ADDR, RESET_TX);
1433 	msm_hs_write(uport, UARTDM_CR_ADDR, RESET_RX);
1434 	msm_hs_write(uport, UARTDM_CR_ADDR, RESET_ERROR_STATUS);
1435 	msm_hs_write(uport, UARTDM_CR_ADDR, RESET_BREAK_INT);
1436 	msm_hs_write(uport, UARTDM_CR_ADDR, RESET_STALE_INT);
1437 	msm_hs_write(uport, UARTDM_CR_ADDR, RESET_CTS);
1438 	msm_hs_write(uport, UARTDM_CR_ADDR, RFR_LOW);
1439 	/* Turn on Uart Receiver */
1440 	msm_hs_write(uport, UARTDM_CR_ADDR, UARTDM_CR_RX_EN_BMSK);
1441 
1442 	/* Turn on Uart Transmitter */
1443 	msm_hs_write(uport, UARTDM_CR_ADDR, UARTDM_CR_TX_EN_BMSK);
1444 
1445 	/* Initialize the tx */
1446 	tx->tx_ready_int_en = 0;
1447 	tx->dma_in_flight = 0;
1448 
1449 	tx->xfer.complete_func = msm_hs_dmov_tx_callback;
1450 	tx->xfer.execute_func = NULL;
1451 
1452 	tx->command_ptr->cmd = CMD_LC |
1453 	    CMD_DST_CRCI(msm_uport->dma_tx_crci) | CMD_MODE_BOX;
1454 
1455 	tx->command_ptr->src_dst_len = (MSM_UARTDM_BURST_SIZE << 16)
1456 					   | (MSM_UARTDM_BURST_SIZE);
1457 
1458 	tx->command_ptr->row_offset = (MSM_UARTDM_BURST_SIZE << 16);
1459 
1460 	tx->command_ptr->dst_row_addr =
1461 	    msm_uport->uport.mapbase + UARTDM_TF_ADDR;
1462 
1463 
1464 	/* Turn on Uart Receive */
1465 	rx->xfer.complete_func = msm_hs_dmov_rx_callback;
1466 	rx->xfer.execute_func = NULL;
1467 
1468 	rx->command_ptr->cmd = CMD_LC |
1469 	    CMD_SRC_CRCI(msm_uport->dma_rx_crci) | CMD_MODE_BOX;
1470 
1471 	rx->command_ptr->src_dst_len = (MSM_UARTDM_BURST_SIZE << 16)
1472 					   | (MSM_UARTDM_BURST_SIZE);
1473 	rx->command_ptr->row_offset =  MSM_UARTDM_BURST_SIZE;
1474 	rx->command_ptr->src_row_addr = uport->mapbase + UARTDM_RF_ADDR;
1475 
1476 
1477 	msm_uport->imr_reg |= UARTDM_ISR_RXSTALE_BMSK;
1478 	/* Enable reading the current CTS, no harm even if CTS is ignored */
1479 	msm_uport->imr_reg |= UARTDM_ISR_CURRENT_CTS_BMSK;
1480 
1481 	msm_hs_write(uport, UARTDM_TFWR_ADDR, 0);  /* TXLEV on empty TX fifo */
1482 
1483 
1484 	ret = request_irq(uport->irq, msm_hs_isr, IRQF_TRIGGER_HIGH,
1485 			  "msm_hs_uart", msm_uport);
1486 	if (unlikely(ret)) {
1487 		printk(KERN_ERR "Request msm_hs_uart IRQ failed!\n");
1488 		goto err_request_irq;
1489 	}
1490 	if (use_low_power_rx_wakeup(msm_uport)) {
1491 		ret = request_irq(msm_uport->rx_wakeup.irq,
1492 				  msm_hs_rx_wakeup_isr,
1493 				  IRQF_TRIGGER_FALLING,
1494 				  "msm_hs_rx_wakeup", msm_uport);
1495 		if (unlikely(ret)) {
1496 			printk(KERN_ERR "Request msm_hs_rx_wakeup IRQ failed!\n");
1497 			free_irq(uport->irq, msm_uport);
1498 			goto err_request_irq;
1499 		}
1500 		disable_irq(msm_uport->rx_wakeup.irq);
1501 	}
1502 
1503 	spin_lock_irqsave(&uport->lock, flags);
1504 
1505 	msm_hs_write(uport, UARTDM_RFWR_ADDR, 0);
1506 	msm_hs_start_rx_locked(uport);
1507 
1508 	spin_unlock_irqrestore(&uport->lock, flags);
1509 	ret = pm_runtime_set_active(uport->dev);
1510 	if (ret)
1511 		dev_err(uport->dev, "set active error:%d\n", ret);
1512 	pm_runtime_enable(uport->dev);
1513 
1514 	return 0;
1515 
1516 err_request_irq:
1517 err_msm_hs_init_clk:
1518 	dma_unmap_single(uport->dev, tx->dma_base,
1519 				UART_XMIT_SIZE, DMA_TO_DEVICE);
1520 	return ret;
1521 }
1522 
1523 /* Initialize tx and rx data structures */
uartdm_init_port(struct uart_port * uport)1524 static int __devinit uartdm_init_port(struct uart_port *uport)
1525 {
1526 	int ret = 0;
1527 	struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport);
1528 	struct msm_hs_tx *tx = &msm_uport->tx;
1529 	struct msm_hs_rx *rx = &msm_uport->rx;
1530 
1531 	/* Allocate the command pointer. Needs to be 64 bit aligned */
1532 	tx->command_ptr = kmalloc(sizeof(dmov_box), GFP_KERNEL | __GFP_DMA);
1533 	if (!tx->command_ptr)
1534 		return -ENOMEM;
1535 
1536 	tx->command_ptr_ptr = kmalloc(sizeof(u32), GFP_KERNEL | __GFP_DMA);
1537 	if (!tx->command_ptr_ptr) {
1538 		ret = -ENOMEM;
1539 		goto err_tx_command_ptr_ptr;
1540 	}
1541 
1542 	tx->mapped_cmd_ptr = dma_map_single(uport->dev, tx->command_ptr,
1543 					    sizeof(dmov_box), DMA_TO_DEVICE);
1544 	tx->mapped_cmd_ptr_ptr = dma_map_single(uport->dev,
1545 						tx->command_ptr_ptr,
1546 						sizeof(u32), DMA_TO_DEVICE);
1547 	tx->xfer.cmdptr = DMOV_CMD_ADDR(tx->mapped_cmd_ptr_ptr);
1548 
1549 	init_waitqueue_head(&rx->wait);
1550 
1551 	rx->pool = dma_pool_create("rx_buffer_pool", uport->dev,
1552 				   UARTDM_RX_BUF_SIZE, 16, 0);
1553 	if (!rx->pool) {
1554 		pr_err("%s(): cannot allocate rx_buffer_pool", __func__);
1555 		ret = -ENOMEM;
1556 		goto err_dma_pool_create;
1557 	}
1558 
1559 	rx->buffer = dma_pool_alloc(rx->pool, GFP_KERNEL, &rx->rbuffer);
1560 	if (!rx->buffer) {
1561 		pr_err("%s(): cannot allocate rx->buffer", __func__);
1562 		ret = -ENOMEM;
1563 		goto err_dma_pool_alloc;
1564 	}
1565 
1566 	/* Allocate the command pointer. Needs to be 64 bit aligned */
1567 	rx->command_ptr = kmalloc(sizeof(dmov_box), GFP_KERNEL | __GFP_DMA);
1568 	if (!rx->command_ptr) {
1569 		pr_err("%s(): cannot allocate rx->command_ptr", __func__);
1570 		ret = -ENOMEM;
1571 		goto err_rx_command_ptr;
1572 	}
1573 
1574 	rx->command_ptr_ptr = kmalloc(sizeof(u32), GFP_KERNEL | __GFP_DMA);
1575 	if (!rx->command_ptr_ptr) {
1576 		pr_err("%s(): cannot allocate rx->command_ptr_ptr", __func__);
1577 		ret = -ENOMEM;
1578 		goto err_rx_command_ptr_ptr;
1579 	}
1580 
1581 	rx->command_ptr->num_rows = ((UARTDM_RX_BUF_SIZE >> 4) << 16) |
1582 					 (UARTDM_RX_BUF_SIZE >> 4);
1583 
1584 	rx->command_ptr->dst_row_addr = rx->rbuffer;
1585 
1586 	rx->mapped_cmd_ptr = dma_map_single(uport->dev, rx->command_ptr,
1587 					    sizeof(dmov_box), DMA_TO_DEVICE);
1588 
1589 	*rx->command_ptr_ptr = CMD_PTR_LP | DMOV_CMD_ADDR(rx->mapped_cmd_ptr);
1590 
1591 	rx->cmdptr_dmaaddr = dma_map_single(uport->dev, rx->command_ptr_ptr,
1592 					    sizeof(u32), DMA_TO_DEVICE);
1593 	rx->xfer.cmdptr = DMOV_CMD_ADDR(rx->cmdptr_dmaaddr);
1594 
1595 	INIT_WORK(&rx->tty_work, msm_hs_tty_flip_buffer_work);
1596 
1597 	return ret;
1598 
1599 err_rx_command_ptr_ptr:
1600 	kfree(rx->command_ptr);
1601 err_rx_command_ptr:
1602 	dma_pool_free(msm_uport->rx.pool, msm_uport->rx.buffer,
1603 						msm_uport->rx.rbuffer);
1604 err_dma_pool_alloc:
1605 	dma_pool_destroy(msm_uport->rx.pool);
1606 err_dma_pool_create:
1607 	dma_unmap_single(uport->dev, msm_uport->tx.mapped_cmd_ptr_ptr,
1608 				sizeof(u32), DMA_TO_DEVICE);
1609 	dma_unmap_single(uport->dev, msm_uport->tx.mapped_cmd_ptr,
1610 				sizeof(dmov_box), DMA_TO_DEVICE);
1611 	kfree(msm_uport->tx.command_ptr_ptr);
1612 err_tx_command_ptr_ptr:
1613 	kfree(msm_uport->tx.command_ptr);
1614 	return ret;
1615 }
1616 
msm_hs_probe(struct platform_device * pdev)1617 static int __devinit msm_hs_probe(struct platform_device *pdev)
1618 {
1619 	int ret;
1620 	struct uart_port *uport;
1621 	struct msm_hs_port *msm_uport;
1622 	struct resource *resource;
1623 	const struct msm_serial_hs_platform_data *pdata =
1624 						pdev->dev.platform_data;
1625 
1626 	if (pdev->id < 0 || pdev->id >= UARTDM_NR) {
1627 		printk(KERN_ERR "Invalid plaform device ID = %d\n", pdev->id);
1628 		return -EINVAL;
1629 	}
1630 
1631 	msm_uport = &q_uart_port[pdev->id];
1632 	uport = &msm_uport->uport;
1633 
1634 	uport->dev = &pdev->dev;
1635 
1636 	resource = platform_get_resource(pdev, IORESOURCE_MEM, 0);
1637 	if (unlikely(!resource))
1638 		return -ENXIO;
1639 
1640 	uport->mapbase = resource->start;
1641 	uport->irq = platform_get_irq(pdev, 0);
1642 	if (unlikely(uport->irq < 0))
1643 		return -ENXIO;
1644 
1645 	if (unlikely(irq_set_irq_wake(uport->irq, 1)))
1646 		return -ENXIO;
1647 
1648 	if (pdata == NULL || pdata->rx_wakeup_irq < 0)
1649 		msm_uport->rx_wakeup.irq = -1;
1650 	else {
1651 		msm_uport->rx_wakeup.irq = pdata->rx_wakeup_irq;
1652 		msm_uport->rx_wakeup.ignore = 1;
1653 		msm_uport->rx_wakeup.inject_rx = pdata->inject_rx_on_wakeup;
1654 		msm_uport->rx_wakeup.rx_to_inject = pdata->rx_to_inject;
1655 
1656 		if (unlikely(msm_uport->rx_wakeup.irq < 0))
1657 			return -ENXIO;
1658 
1659 		if (unlikely(irq_set_irq_wake(msm_uport->rx_wakeup.irq, 1)))
1660 			return -ENXIO;
1661 	}
1662 
1663 	if (pdata == NULL)
1664 		msm_uport->exit_lpm_cb = NULL;
1665 	else
1666 		msm_uport->exit_lpm_cb = pdata->exit_lpm_cb;
1667 
1668 	resource = platform_get_resource_byname(pdev, IORESOURCE_DMA,
1669 						"uartdm_channels");
1670 	if (unlikely(!resource))
1671 		return -ENXIO;
1672 
1673 	msm_uport->dma_tx_channel = resource->start;
1674 	msm_uport->dma_rx_channel = resource->end;
1675 
1676 	resource = platform_get_resource_byname(pdev, IORESOURCE_DMA,
1677 						"uartdm_crci");
1678 	if (unlikely(!resource))
1679 		return -ENXIO;
1680 
1681 	msm_uport->dma_tx_crci = resource->start;
1682 	msm_uport->dma_rx_crci = resource->end;
1683 
1684 	uport->iotype = UPIO_MEM;
1685 	uport->fifosize = UART_FIFOSIZE;
1686 	uport->ops = &msm_hs_ops;
1687 	uport->flags = UPF_BOOT_AUTOCONF;
1688 	uport->uartclk = UARTCLK;
1689 	msm_uport->imr_reg = 0x0;
1690 	msm_uport->clk = clk_get(&pdev->dev, "uartdm_clk");
1691 	if (IS_ERR(msm_uport->clk))
1692 		return PTR_ERR(msm_uport->clk);
1693 
1694 	ret = uartdm_init_port(uport);
1695 	if (unlikely(ret))
1696 		return ret;
1697 
1698 	msm_uport->clk_state = MSM_HS_CLK_PORT_OFF;
1699 	hrtimer_init(&msm_uport->clk_off_timer, CLOCK_MONOTONIC,
1700 		     HRTIMER_MODE_REL);
1701 	msm_uport->clk_off_timer.function = msm_hs_clk_off_retry;
1702 	msm_uport->clk_off_delay = ktime_set(0, 1000000);  /* 1ms */
1703 
1704 	uport->line = pdev->id;
1705 	return uart_add_one_port(&msm_hs_driver, uport);
1706 }
1707 
msm_serial_hs_init(void)1708 static int __init msm_serial_hs_init(void)
1709 {
1710 	int ret, i;
1711 
1712 	/* Init all UARTS as non-configured */
1713 	for (i = 0; i < UARTDM_NR; i++)
1714 		q_uart_port[i].uport.type = PORT_UNKNOWN;
1715 
1716 	msm_hs_workqueue = create_singlethread_workqueue("msm_serial_hs");
1717 	if (unlikely(!msm_hs_workqueue))
1718 		return -ENOMEM;
1719 
1720 	ret = uart_register_driver(&msm_hs_driver);
1721 	if (unlikely(ret)) {
1722 		printk(KERN_ERR "%s failed to load\n", __func__);
1723 		goto err_uart_register_driver;
1724 	}
1725 
1726 	ret = platform_driver_register(&msm_serial_hs_platform_driver);
1727 	if (ret) {
1728 		printk(KERN_ERR "%s failed to load\n", __func__);
1729 		goto err_platform_driver_register;
1730 	}
1731 
1732 	return ret;
1733 
1734 err_platform_driver_register:
1735 	uart_unregister_driver(&msm_hs_driver);
1736 err_uart_register_driver:
1737 	destroy_workqueue(msm_hs_workqueue);
1738 	return ret;
1739 }
1740 module_init(msm_serial_hs_init);
1741 
1742 /*
1743  *  Called by the upper layer when port is closed.
1744  *     - Disables the port
1745  *     - Unhook the ISR
1746  */
msm_hs_shutdown(struct uart_port * uport)1747 static void msm_hs_shutdown(struct uart_port *uport)
1748 {
1749 	unsigned long flags;
1750 	struct msm_hs_port *msm_uport = UARTDM_TO_MSM(uport);
1751 
1752 	BUG_ON(msm_uport->rx.flush < FLUSH_STOP);
1753 
1754 	spin_lock_irqsave(&uport->lock, flags);
1755 	clk_enable(msm_uport->clk);
1756 
1757 	/* Disable the transmitter */
1758 	msm_hs_write(uport, UARTDM_CR_ADDR, UARTDM_CR_TX_DISABLE_BMSK);
1759 	/* Disable the receiver */
1760 	msm_hs_write(uport, UARTDM_CR_ADDR, UARTDM_CR_RX_DISABLE_BMSK);
1761 
1762 	pm_runtime_disable(uport->dev);
1763 	pm_runtime_set_suspended(uport->dev);
1764 
1765 	/* Free the interrupt */
1766 	free_irq(uport->irq, msm_uport);
1767 	if (use_low_power_rx_wakeup(msm_uport))
1768 		free_irq(msm_uport->rx_wakeup.irq, msm_uport);
1769 
1770 	msm_uport->imr_reg = 0;
1771 	msm_hs_write(uport, UARTDM_IMR_ADDR, msm_uport->imr_reg);
1772 
1773 	wait_event(msm_uport->rx.wait, msm_uport->rx.flush == FLUSH_SHUTDOWN);
1774 
1775 	clk_disable(msm_uport->clk);  /* to balance local clk_enable() */
1776 	if (msm_uport->clk_state != MSM_HS_CLK_OFF)
1777 		clk_disable(msm_uport->clk);  /* to balance clk_state */
1778 	msm_uport->clk_state = MSM_HS_CLK_PORT_OFF;
1779 
1780 	dma_unmap_single(uport->dev, msm_uport->tx.dma_base,
1781 			 UART_XMIT_SIZE, DMA_TO_DEVICE);
1782 
1783 	spin_unlock_irqrestore(&uport->lock, flags);
1784 
1785 	if (cancel_work_sync(&msm_uport->rx.tty_work))
1786 		msm_hs_tty_flip_buffer_work(&msm_uport->rx.tty_work);
1787 }
1788 
msm_serial_hs_exit(void)1789 static void __exit msm_serial_hs_exit(void)
1790 {
1791 	flush_workqueue(msm_hs_workqueue);
1792 	destroy_workqueue(msm_hs_workqueue);
1793 	platform_driver_unregister(&msm_serial_hs_platform_driver);
1794 	uart_unregister_driver(&msm_hs_driver);
1795 }
1796 module_exit(msm_serial_hs_exit);
1797 
1798 #ifdef CONFIG_PM_RUNTIME
msm_hs_runtime_idle(struct device * dev)1799 static int msm_hs_runtime_idle(struct device *dev)
1800 {
1801 	/*
1802 	 * returning success from idle results in runtime suspend to be
1803 	 * called
1804 	 */
1805 	return 0;
1806 }
1807 
msm_hs_runtime_resume(struct device * dev)1808 static int msm_hs_runtime_resume(struct device *dev)
1809 {
1810 	struct platform_device *pdev = container_of(dev, struct
1811 						    platform_device, dev);
1812 	struct msm_hs_port *msm_uport = &q_uart_port[pdev->id];
1813 
1814 	msm_hs_request_clock_on(&msm_uport->uport);
1815 	return 0;
1816 }
1817 
msm_hs_runtime_suspend(struct device * dev)1818 static int msm_hs_runtime_suspend(struct device *dev)
1819 {
1820 	struct platform_device *pdev = container_of(dev, struct
1821 						    platform_device, dev);
1822 	struct msm_hs_port *msm_uport = &q_uart_port[pdev->id];
1823 
1824 	msm_hs_request_clock_off(&msm_uport->uport);
1825 	return 0;
1826 }
1827 #else
1828 #define msm_hs_runtime_idle NULL
1829 #define msm_hs_runtime_resume NULL
1830 #define msm_hs_runtime_suspend NULL
1831 #endif
1832 
1833 static const struct dev_pm_ops msm_hs_dev_pm_ops = {
1834 	.runtime_suspend = msm_hs_runtime_suspend,
1835 	.runtime_resume  = msm_hs_runtime_resume,
1836 	.runtime_idle    = msm_hs_runtime_idle,
1837 };
1838 
1839 static struct platform_driver msm_serial_hs_platform_driver = {
1840 	.probe = msm_hs_probe,
1841 	.remove = __devexit_p(msm_hs_remove),
1842 	.driver = {
1843 		.name = "msm_serial_hs",
1844 		.owner = THIS_MODULE,
1845 		.pm   = &msm_hs_dev_pm_ops,
1846 	},
1847 };
1848 
1849 static struct uart_driver msm_hs_driver = {
1850 	.owner = THIS_MODULE,
1851 	.driver_name = "msm_serial_hs",
1852 	.dev_name = "ttyHS",
1853 	.nr = UARTDM_NR,
1854 	.cons = 0,
1855 };
1856 
1857 static struct uart_ops msm_hs_ops = {
1858 	.tx_empty = msm_hs_tx_empty,
1859 	.set_mctrl = msm_hs_set_mctrl_locked,
1860 	.get_mctrl = msm_hs_get_mctrl_locked,
1861 	.stop_tx = msm_hs_stop_tx_locked,
1862 	.start_tx = msm_hs_start_tx_locked,
1863 	.stop_rx = msm_hs_stop_rx_locked,
1864 	.enable_ms = msm_hs_enable_ms_locked,
1865 	.break_ctl = msm_hs_break_ctl,
1866 	.startup = msm_hs_startup,
1867 	.shutdown = msm_hs_shutdown,
1868 	.set_termios = msm_hs_set_termios,
1869 	.pm = msm_hs_pm,
1870 	.type = msm_hs_type,
1871 	.config_port = msm_hs_config_port,
1872 	.release_port = msm_hs_release_port,
1873 	.request_port = msm_hs_request_port,
1874 };
1875 
1876 MODULE_DESCRIPTION("High Speed UART Driver for the MSM chipset");
1877 MODULE_VERSION("1.2");
1878 MODULE_LICENSE("GPL v2");
1879