1 /*
2  * Wireless Host Controller (WHC) hardware access helpers.
3  *
4  * Copyright (C) 2007 Cambridge Silicon Radio Ltd.
5  *
6  * This program is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU General Public License version
8  * 2 as published by the Free Software Foundation.
9  *
10  * This program is distributed in the hope that it will be useful,
11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
13  * GNU General Public License for more details.
14  *
15  * You should have received a copy of the GNU General Public License
16  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
17  */
18 #include <linux/kernel.h>
19 #include <linux/dma-mapping.h>
20 #include <linux/uwb/umc.h>
21 
22 #include "../../wusbcore/wusbhc.h"
23 
24 #include "whcd.h"
25 
whc_write_wusbcmd(struct whc * whc,u32 mask,u32 val)26 void whc_write_wusbcmd(struct whc *whc, u32 mask, u32 val)
27 {
28 	unsigned long flags;
29 	u32 cmd;
30 
31 	spin_lock_irqsave(&whc->lock, flags);
32 
33 	cmd = le_readl(whc->base + WUSBCMD);
34 	cmd = (cmd & ~mask) | val;
35 	le_writel(cmd, whc->base + WUSBCMD);
36 
37 	spin_unlock_irqrestore(&whc->lock, flags);
38 }
39 
40 /**
41  * whc_do_gencmd - start a generic command via the WUSBGENCMDSTS register
42  * @whc:    the WHCI HC
43  * @cmd:    command to start.
44  * @params: parameters for the command (the WUSBGENCMDPARAMS register value).
45  * @addr:   pointer to any data for the command (may be NULL).
46  * @len:    length of the data (if any).
47  */
whc_do_gencmd(struct whc * whc,u32 cmd,u32 params,void * addr,size_t len)48 int whc_do_gencmd(struct whc *whc, u32 cmd, u32 params, void *addr, size_t len)
49 {
50 	unsigned long flags;
51 	dma_addr_t dma_addr;
52 	int t;
53 	int ret = 0;
54 
55 	mutex_lock(&whc->mutex);
56 
57 	/* Wait for previous command to complete. */
58 	t = wait_event_timeout(whc->cmd_wq,
59 			       (le_readl(whc->base + WUSBGENCMDSTS) & WUSBGENCMDSTS_ACTIVE) == 0,
60 			       WHC_GENCMD_TIMEOUT_MS);
61 	if (t == 0) {
62 		dev_err(&whc->umc->dev, "generic command timeout (%04x/%04x)\n",
63 			le_readl(whc->base + WUSBGENCMDSTS),
64 			le_readl(whc->base + WUSBGENCMDPARAMS));
65 		ret = -ETIMEDOUT;
66 		goto out;
67 	}
68 
69 	if (addr) {
70 		memcpy(whc->gen_cmd_buf, addr, len);
71 		dma_addr = whc->gen_cmd_buf_dma;
72 	} else
73 		dma_addr = 0;
74 
75 	/* Poke registers to start cmd. */
76 	spin_lock_irqsave(&whc->lock, flags);
77 
78 	le_writel(params, whc->base + WUSBGENCMDPARAMS);
79 	le_writeq(dma_addr, whc->base + WUSBGENADDR);
80 
81 	le_writel(WUSBGENCMDSTS_ACTIVE | WUSBGENCMDSTS_IOC | cmd,
82 		  whc->base + WUSBGENCMDSTS);
83 
84 	spin_unlock_irqrestore(&whc->lock, flags);
85 out:
86 	mutex_unlock(&whc->mutex);
87 
88 	return ret;
89 }
90 
91 /**
92  * whc_hw_error - recover from a hardware error
93  * @whc:    the WHCI HC that broke.
94  * @reason: a description of the failure.
95  *
96  * Recover from broken hardware with a full reset.
97  */
whc_hw_error(struct whc * whc,const char * reason)98 void whc_hw_error(struct whc *whc, const char *reason)
99 {
100 	struct wusbhc *wusbhc = &whc->wusbhc;
101 
102 	dev_err(&whc->umc->dev, "hardware error: %s\n", reason);
103 	wusbhc_reset_all(wusbhc);
104 }
105