drivers/usb/host/whci/hw.c

   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
  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  */
  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  */
  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 }