1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3  * TQ-Systems PLD MFD core driver, based on vendor driver by
4  * Vadim V.Vlasov <vvlasov@dev.rtsoft.ru>
5  *
6  * Copyright (c) 2015 TQ-Systems GmbH
7  * Copyright (c) 2019 Andrew Lunn <andrew@lunn.ch>
8  */
9 
10 #include <linux/delay.h>
11 #include <linux/dmi.h>
12 #include <linux/i2c.h>
13 #include <linux/io.h>
14 #include <linux/mfd/core.h>
15 #include <linux/module.h>
16 #include <linux/platform_data/i2c-ocores.h>
17 #include <linux/platform_device.h>
18 
19 #define TQMX86_IOBASE	0x180
20 #define TQMX86_IOSIZE	0x20
21 #define TQMX86_IOBASE_I2C	0x1a0
22 #define TQMX86_IOSIZE_I2C	0xa
23 #define TQMX86_IOBASE_WATCHDOG	0x18b
24 #define TQMX86_IOSIZE_WATCHDOG	0x2
25 #define TQMX86_IOBASE_GPIO	0x18d
26 #define TQMX86_IOSIZE_GPIO	0x4
27 
28 #define TQMX86_REG_BOARD_ID	0x00
29 #define TQMX86_REG_BOARD_ID_E38M	1
30 #define TQMX86_REG_BOARD_ID_50UC	2
31 #define TQMX86_REG_BOARD_ID_E38C	3
32 #define TQMX86_REG_BOARD_ID_60EB	4
33 #define TQMX86_REG_BOARD_ID_E39MS	5
34 #define TQMX86_REG_BOARD_ID_E39C1	6
35 #define TQMX86_REG_BOARD_ID_E39C2	7
36 #define TQMX86_REG_BOARD_ID_70EB	8
37 #define TQMX86_REG_BOARD_ID_80UC	9
38 #define TQMX86_REG_BOARD_ID_110EB	11
39 #define TQMX86_REG_BOARD_ID_E40M	12
40 #define TQMX86_REG_BOARD_ID_E40S	13
41 #define TQMX86_REG_BOARD_ID_E40C1	14
42 #define TQMX86_REG_BOARD_ID_E40C2	15
43 #define TQMX86_REG_BOARD_REV	0x01
44 #define TQMX86_REG_IO_EXT_INT	0x06
45 #define TQMX86_REG_IO_EXT_INT_NONE		0
46 #define TQMX86_REG_IO_EXT_INT_7			1
47 #define TQMX86_REG_IO_EXT_INT_9			2
48 #define TQMX86_REG_IO_EXT_INT_12		3
49 #define TQMX86_REG_IO_EXT_INT_MASK		0x3
50 #define TQMX86_REG_IO_EXT_INT_GPIO_SHIFT	4
51 #define TQMX86_REG_SAUC		0x17
52 
53 #define TQMX86_REG_I2C_DETECT	0x1a7
54 #define TQMX86_REG_I2C_DETECT_SOFT		0xa5
55 
56 static uint gpio_irq;
57 module_param(gpio_irq, uint, 0);
58 MODULE_PARM_DESC(gpio_irq, "GPIO IRQ number (7, 9, 12)");
59 
60 static const struct resource tqmx_i2c_soft_resources[] = {
61 	DEFINE_RES_IO(TQMX86_IOBASE_I2C, TQMX86_IOSIZE_I2C),
62 };
63 
64 static const struct resource tqmx_watchdog_resources[] = {
65 	DEFINE_RES_IO(TQMX86_IOBASE_WATCHDOG, TQMX86_IOSIZE_WATCHDOG),
66 };
67 
68 /*
69  * The IRQ resource must be first, since it is updated with the
70  * configured IRQ in the probe function.
71  */
72 static struct resource tqmx_gpio_resources[] = {
73 	DEFINE_RES_IRQ(0),
74 	DEFINE_RES_IO(TQMX86_IOBASE_GPIO, TQMX86_IOSIZE_GPIO),
75 };
76 
77 static struct i2c_board_info tqmx86_i2c_devices[] = {
78 	{
79 		/* 4K EEPROM at 0x50 */
80 		I2C_BOARD_INFO("24c32", 0x50),
81 	},
82 };
83 
84 static struct ocores_i2c_platform_data ocores_platform_data = {
85 	.num_devices = ARRAY_SIZE(tqmx86_i2c_devices),
86 	.devices = tqmx86_i2c_devices,
87 };
88 
89 static const struct mfd_cell tqmx86_i2c_soft_dev[] = {
90 	{
91 		.name = "ocores-i2c",
92 		.platform_data = &ocores_platform_data,
93 		.pdata_size = sizeof(ocores_platform_data),
94 		.resources = tqmx_i2c_soft_resources,
95 		.num_resources = ARRAY_SIZE(tqmx_i2c_soft_resources),
96 	},
97 };
98 
99 static const struct mfd_cell tqmx86_devs[] = {
100 	{
101 		.name = "tqmx86-wdt",
102 		.resources = tqmx_watchdog_resources,
103 		.num_resources = ARRAY_SIZE(tqmx_watchdog_resources),
104 		.ignore_resource_conflicts = true,
105 	},
106 	{
107 		.name = "tqmx86-gpio",
108 		.resources = tqmx_gpio_resources,
109 		.num_resources = ARRAY_SIZE(tqmx_gpio_resources),
110 		.ignore_resource_conflicts = true,
111 	},
112 };
113 
tqmx86_board_id_to_name(u8 board_id,u8 sauc)114 static const char *tqmx86_board_id_to_name(u8 board_id, u8 sauc)
115 {
116 	switch (board_id) {
117 	case TQMX86_REG_BOARD_ID_E38M:
118 		return "TQMxE38M";
119 	case TQMX86_REG_BOARD_ID_50UC:
120 		return "TQMx50UC";
121 	case TQMX86_REG_BOARD_ID_E38C:
122 		return "TQMxE38C";
123 	case TQMX86_REG_BOARD_ID_60EB:
124 		return "TQMx60EB";
125 	case TQMX86_REG_BOARD_ID_E39MS:
126 		return (sauc == 0xff) ? "TQMxE39M" : "TQMxE39S";
127 	case TQMX86_REG_BOARD_ID_E39C1:
128 		return "TQMxE39C1";
129 	case TQMX86_REG_BOARD_ID_E39C2:
130 		return "TQMxE39C2";
131 	case TQMX86_REG_BOARD_ID_70EB:
132 		return "TQMx70EB";
133 	case TQMX86_REG_BOARD_ID_80UC:
134 		return "TQMx80UC";
135 	case TQMX86_REG_BOARD_ID_110EB:
136 		return "TQMx110EB";
137 	case TQMX86_REG_BOARD_ID_E40M:
138 		return "TQMxE40M";
139 	case TQMX86_REG_BOARD_ID_E40S:
140 		return "TQMxE40S";
141 	case TQMX86_REG_BOARD_ID_E40C1:
142 		return "TQMxE40C1";
143 	case TQMX86_REG_BOARD_ID_E40C2:
144 		return "TQMxE40C2";
145 	default:
146 		return "Unknown";
147 	}
148 }
149 
tqmx86_board_id_to_clk_rate(struct device * dev,u8 board_id)150 static int tqmx86_board_id_to_clk_rate(struct device *dev, u8 board_id)
151 {
152 	switch (board_id) {
153 	case TQMX86_REG_BOARD_ID_50UC:
154 	case TQMX86_REG_BOARD_ID_60EB:
155 	case TQMX86_REG_BOARD_ID_70EB:
156 	case TQMX86_REG_BOARD_ID_80UC:
157 	case TQMX86_REG_BOARD_ID_110EB:
158 	case TQMX86_REG_BOARD_ID_E40M:
159 	case TQMX86_REG_BOARD_ID_E40S:
160 	case TQMX86_REG_BOARD_ID_E40C1:
161 	case TQMX86_REG_BOARD_ID_E40C2:
162 		return 24000;
163 	case TQMX86_REG_BOARD_ID_E39MS:
164 	case TQMX86_REG_BOARD_ID_E39C1:
165 	case TQMX86_REG_BOARD_ID_E39C2:
166 		return 25000;
167 	case TQMX86_REG_BOARD_ID_E38M:
168 	case TQMX86_REG_BOARD_ID_E38C:
169 		return 33000;
170 	default:
171 		dev_warn(dev, "unknown board %d, assuming 24MHz LPC clock\n",
172 			 board_id);
173 		return 24000;
174 	}
175 }
176 
tqmx86_probe(struct platform_device * pdev)177 static int tqmx86_probe(struct platform_device *pdev)
178 {
179 	u8 board_id, sauc, rev, i2c_det, io_ext_int_val;
180 	struct device *dev = &pdev->dev;
181 	u8 gpio_irq_cfg, readback;
182 	const char *board_name;
183 	void __iomem *io_base;
184 	int err;
185 
186 	switch (gpio_irq) {
187 	case 0:
188 		gpio_irq_cfg = TQMX86_REG_IO_EXT_INT_NONE;
189 		break;
190 	case 7:
191 		gpio_irq_cfg = TQMX86_REG_IO_EXT_INT_7;
192 		break;
193 	case 9:
194 		gpio_irq_cfg = TQMX86_REG_IO_EXT_INT_9;
195 		break;
196 	case 12:
197 		gpio_irq_cfg = TQMX86_REG_IO_EXT_INT_12;
198 		break;
199 	default:
200 		pr_err("tqmx86: Invalid GPIO IRQ (%d)\n", gpio_irq);
201 		return -EINVAL;
202 	}
203 
204 	io_base = devm_ioport_map(dev, TQMX86_IOBASE, TQMX86_IOSIZE);
205 	if (!io_base)
206 		return -ENOMEM;
207 
208 	board_id = ioread8(io_base + TQMX86_REG_BOARD_ID);
209 	sauc = ioread8(io_base + TQMX86_REG_SAUC);
210 	board_name = tqmx86_board_id_to_name(board_id, sauc);
211 	rev = ioread8(io_base + TQMX86_REG_BOARD_REV);
212 
213 	dev_info(dev,
214 		 "Found %s - Board ID %d, PCB Revision %d, PLD Revision %d\n",
215 		 board_name, board_id, rev >> 4, rev & 0xf);
216 
217 	/*
218 	 * The I2C_DETECT register is in the range assigned to the I2C driver
219 	 * later, so we don't extend TQMX86_IOSIZE. Use inb() for this one-off
220 	 * access instead of ioport_map + unmap.
221 	 */
222 	i2c_det = inb(TQMX86_REG_I2C_DETECT);
223 
224 	if (gpio_irq_cfg) {
225 		io_ext_int_val =
226 			gpio_irq_cfg << TQMX86_REG_IO_EXT_INT_GPIO_SHIFT;
227 		iowrite8(io_ext_int_val, io_base + TQMX86_REG_IO_EXT_INT);
228 		readback = ioread8(io_base + TQMX86_REG_IO_EXT_INT);
229 		if (readback != io_ext_int_val) {
230 			dev_warn(dev, "GPIO interrupts not supported.\n");
231 			return -EINVAL;
232 		}
233 
234 		/* Assumes the IRQ resource is first. */
235 		tqmx_gpio_resources[0].start = gpio_irq;
236 	} else {
237 		tqmx_gpio_resources[0].flags = 0;
238 	}
239 
240 	ocores_platform_data.clock_khz = tqmx86_board_id_to_clk_rate(dev, board_id);
241 
242 	if (i2c_det == TQMX86_REG_I2C_DETECT_SOFT) {
243 		err = devm_mfd_add_devices(dev, PLATFORM_DEVID_NONE,
244 					   tqmx86_i2c_soft_dev,
245 					   ARRAY_SIZE(tqmx86_i2c_soft_dev),
246 					   NULL, 0, NULL);
247 		if (err)
248 			return err;
249 	}
250 
251 	return devm_mfd_add_devices(dev, PLATFORM_DEVID_NONE,
252 				    tqmx86_devs,
253 				    ARRAY_SIZE(tqmx86_devs),
254 				    NULL, 0, NULL);
255 }
256 
tqmx86_create_platform_device(const struct dmi_system_id * id)257 static int tqmx86_create_platform_device(const struct dmi_system_id *id)
258 {
259 	struct platform_device *pdev;
260 	int err;
261 
262 	pdev = platform_device_alloc("tqmx86", -1);
263 	if (!pdev)
264 		return -ENOMEM;
265 
266 	err = platform_device_add(pdev);
267 	if (err)
268 		platform_device_put(pdev);
269 
270 	return err;
271 }
272 
273 static const struct dmi_system_id tqmx86_dmi_table[] __initconst = {
274 	{
275 		.ident = "TQMX86",
276 		.matches = {
277 			DMI_MATCH(DMI_SYS_VENDOR, "TQ-Group"),
278 			DMI_MATCH(DMI_PRODUCT_NAME, "TQMx"),
279 		},
280 		.callback = tqmx86_create_platform_device,
281 	},
282 	{
283 		.ident = "TQMX86",
284 		.matches = {
285 			DMI_MATCH(DMI_SYS_VENDOR, "TQ-Systems"),
286 			DMI_MATCH(DMI_PRODUCT_NAME, "TQMx"),
287 		},
288 		.callback = tqmx86_create_platform_device,
289 	},
290 	{}
291 };
292 MODULE_DEVICE_TABLE(dmi, tqmx86_dmi_table);
293 
294 static struct platform_driver tqmx86_driver = {
295 	.driver		= {
296 		.name	= "tqmx86",
297 	},
298 	.probe		= tqmx86_probe,
299 };
300 
tqmx86_init(void)301 static int __init tqmx86_init(void)
302 {
303 	if (!dmi_check_system(tqmx86_dmi_table))
304 		return -ENODEV;
305 
306 	return platform_driver_register(&tqmx86_driver);
307 }
308 
309 module_init(tqmx86_init);
310 
311 MODULE_DESCRIPTION("TQMx86 PLD Core Driver");
312 MODULE_AUTHOR("Andrew Lunn <andrew@lunn.ch>");
313 MODULE_LICENSE("GPL");
314 MODULE_ALIAS("platform:tqmx86");
315