target/linux/sunxi/patches-3.13/160-5-ahci-platform-devs-with-more-than-1-clock.patch

   1 From bdad8090b5efdb24fa9db00d8e2891927b68dcec Mon Sep 17 00:00:00 2001
   2 From: Hans de Goede <hdegoede@redhat.com>
   3 Date: Thu, 16 Jan 2014 14:32:35 +0100
   4 Subject: [PATCH] ahci-platform: Add support for devices with more then 1 clock
   5
   6 The allwinner-sun4i AHCI controller needs 2 clocks to be enabled and the
   7 imx AHCI controller needs 3 clocks to be enabled.
   8
   9 Signed-off-by: Hans de Goede <hdegoede@redhat.com>
  10 ---
  11  .../devicetree/bindings/ata/ahci-platform.txt      |   1 +
  12  drivers/ata/ahci.h                                 |   3 +-
  13  drivers/ata/ahci_platform.c                        | 119 ++++++++++++++++-----
  14  include/linux/ahci_platform.h                      |   4 +
  15  4 files changed, 99 insertions(+), 28 deletions(-)
  16
  17 diff --git a/Documentation/devicetree/bindings/ata/ahci-platform.txt b/Documentation/devicetree/bindings/ata/ahci-platform.txt
  18 index 89de156..3ced07d 100644
  19 --- a/Documentation/devicetree/bindings/ata/ahci-platform.txt
  20 +++ b/Documentation/devicetree/bindings/ata/ahci-platform.txt
  21 @@ -10,6 +10,7 @@ Required properties:
  22
  23  Optional properties:
  24  - dma-coherent      : Present if dma operations are coherent
  25 +- clocks            : a list of phandle + clock specifier pairs
  26
  27  Example:
  28          sata@ffe08000 {
  29 diff --git a/drivers/ata/ahci.h b/drivers/ata/ahci.h
  30 index 64d1a99d..c12862b 100644
  31 --- a/drivers/ata/ahci.h
  32 +++ b/drivers/ata/ahci.h
  33 @@ -51,6 +51,7 @@
  34
  35  enum {
  36         AHCI_MAX_PORTS          = 32,
  37 +       AHCI_MAX_CLKS           = 3,
  38         AHCI_MAX_SG             = 168, /* hardware max is 64K */
  39         AHCI_DMA_BOUNDARY       = 0xffffffff,
  40         AHCI_MAX_CMDS           = 32,
  41 @@ -321,7 +322,7 @@ struct ahci_host_priv {
  42         u32                     em_loc; /* enclosure management location */
  43         u32                     em_buf_sz;      /* EM buffer size in byte */
  44         u32                     em_msg_type;    /* EM message type */
  45 -       struct clk              *clk;           /* Only for platforms supporting clk */
  46 +       struct clk              *clks[AHCI_MAX_CLKS]; /* Optional */
  47         void                    *plat_data;     /* Other platform data */
  48         /*
  49          * Optional ahci_start_engine override, if not set this gets set to the
  50 diff --git a/drivers/ata/ahci_platform.c b/drivers/ata/ahci_platform.c
  51 index 4b231ba..609975d 100644
  52 --- a/drivers/ata/ahci_platform.c
  53 +++ b/drivers/ata/ahci_platform.c
  54 @@ -87,6 +87,66 @@ struct ata_port_operations ahci_platform_ops = {
  55         AHCI_SHT("ahci_platform"),
  56  };
  57
  58 +/**
  59 + *     ahci_platform_enable_clks - Enable platform clocks
  60 + *     @hpriv: host private area to store config values
  61 + *
  62 + *     This function enables all the clks found in hpriv->clks, starting
  63 + *     at index 0. If any clk fails to enable it disables all the clks
  64 + *     already enabled in reverse order, and then returns an error.
  65 + *
  66 + *     LOCKING:
  67 + *     None.
  68 + *
  69 + *     RETURNS:
  70 + *     0 on success otherwise a negative error code
  71 + */
  72 +int ahci_platform_enable_clks(struct ahci_host_priv *hpriv)
  73 +{
  74 +       int c, rc;
  75 +
  76 +       for (c = 0; c < AHCI_MAX_CLKS && hpriv->clks[c]; c++) {
  77 +               rc = clk_prepare_enable(hpriv->clks[c]);
  78 +               if (rc)
  79 +                       goto disable_unprepare_clk;
  80 +       }
  81 +       return 0;
  82 +
  83 +disable_unprepare_clk:
  84 +       while (--c >= 0)
  85 +               clk_disable_unprepare(hpriv->clks[c]);
  86 +       return rc;
  87 +}
  88 +EXPORT_SYMBOL_GPL(ahci_platform_enable_clks);
  89 +
  90 +/**
  91 + *     ahci_platform_disable_clks - Disable platform clocks
  92 + *     @hpriv: host private area to store config values
  93 + *
  94 + *     This function disables all the clks found in hpriv->clks, in reverse
  95 + *     order of ahci_platform_enable_clks (starting at the end of the array).
  96 + *
  97 + *     LOCKING:
  98 + *     None.
  99 + */
 100 +void ahci_platform_disable_clks(struct ahci_host_priv *hpriv)
 101 +{
 102 +       int c;
 103 +
 104 +       for (c = AHCI_MAX_CLKS - 1; c >= 0; c--)
 105 +               if (hpriv->clks[c])
 106 +                       clk_disable_unprepare(hpriv->clks[c]);
 107 +}
 108 +EXPORT_SYMBOL_GPL(ahci_platform_disable_clks);
 109 +
 110 +static void ahci_put_clks(struct ahci_host_priv *hpriv)
 111 +{
 112 +       int c;
 113 +
 114 +       for (c = 0; c < AHCI_MAX_CLKS && hpriv->clks[c]; c++)
 115 +               clk_put(hpriv->clks[c]);
 116 +}
 117 +
 118  static int ahci_probe(struct platform_device *pdev)
 119  {
 120         struct device *dev = &pdev->dev;
 121 @@ -97,6 +157,7 @@ static int ahci_probe(struct platform_device *pdev)
 122         struct ahci_host_priv *hpriv;
 123         struct ata_host *host;
 124         struct resource *mem;
 125 +       struct clk *clk;
 126         int irq;
 127         int n_ports;
 128         int i;
 129 @@ -131,17 +192,31 @@ static int ahci_probe(struct platform_device *pdev)
 130                 return -ENOMEM;
 131         }
 132
 133 -       hpriv->clk = clk_get(dev, NULL);
 134 -       if (IS_ERR(hpriv->clk)) {
 135 -               dev_err(dev, "can't get clock\n");
 136 -       } else {
 137 -               rc = clk_prepare_enable(hpriv->clk);
 138 -               if (rc) {
 139 -                       dev_err(dev, "clock prepare enable failed");
 140 -                       goto free_clk;
 141 +       for (i = 0; i < AHCI_MAX_CLKS; i++) {
 142 +               /*
 143 +                * For now we must use clk_get(dev, NULL) for the first clock,
 144 +                * because some platforms (da850, spear13xx) are not yet
 145 +                * converted to use devicetree for clocks.  For new platforms
 146 +                * this is equivalent to of_clk_get(dev->of_node, 0).
 147 +                */
 148 +               if (i == 0)
 149 +                       clk = clk_get(dev, NULL);
 150 +               else
 151 +                       clk = of_clk_get(dev->of_node, i);
 152 +
 153 +               if (IS_ERR(clk)) {
 154 +                       rc = PTR_ERR(clk);
 155 +                       if (rc == -EPROBE_DEFER)
 156 +                               goto free_clk;
 157 +                       break;
 158                 }
 159 +               hpriv->clks[i] = clk;
 160         }
 161
 162 +       rc = ahci_enable_clks(dev, hpriv);
 163 +       if (rc)
 164 +               goto free_clk;
 165 +
 166         /*
 167          * Some platforms might need to prepare for mmio region access,
 168          * which could be done in the following init call. So, the mmio
 169 @@ -222,11 +297,9 @@ static int ahci_probe(struct platform_device *pdev)
 170         if (pdata && pdata->exit)
 171                 pdata->exit(dev);
 172  disable_unprepare_clk:
 173 -       if (!IS_ERR(hpriv->clk))
 174 -               clk_disable_unprepare(hpriv->clk);
 175 +       ahci_disable_clks(hpriv);
 176  free_clk:
 177 -       if (!IS_ERR(hpriv->clk))
 178 -               clk_put(hpriv->clk);
 179 +       ahci_put_clks(hpriv);
 180         return rc;
 181  }
 182
 183 @@ -239,10 +312,8 @@ static void ahci_host_stop(struct ata_host *host)
 184         if (pdata && pdata->exit)
 185                 pdata->exit(dev);
 186
 187 -       if (!IS_ERR(hpriv->clk)) {
 188 -               clk_disable_unprepare(hpriv->clk);
 189 -               clk_put(hpriv->clk);
 190 -       }
 191 +       ahci_disable_clks(hpriv);
 192 +       ahci_put_clks(hpriv);
 193  }
 194
 195  #ifdef CONFIG_PM_SLEEP
 196 @@ -277,8 +348,7 @@ static int ahci_suspend(struct device *dev)
 197         if (pdata && pdata->suspend)
 198                 return pdata->suspend(dev);
 199
 200 -       if (!IS_ERR(hpriv->clk))
 201 -               clk_disable_unprepare(hpriv->clk);
 202 +       ahci_disable_clks(hpriv);
 203
 204         return 0;
 205  }
 206 @@ -290,13 +360,9 @@ static int ahci_resume(struct device *dev)
 207         struct ahci_host_priv *hpriv = host->private_data;
 208         int rc;
 209
 210 -       if (!IS_ERR(hpriv->clk)) {
 211 -               rc = clk_prepare_enable(hpriv->clk);
 212 -               if (rc) {
 213 -                       dev_err(dev, "clock prepare enable failed");
 214 -                       return rc;
 215 -               }
 216 -       }
 217 +       rc = ahci_enable_clks(dev, hpriv);
 218 +       if (rc)
 219 +               return rc;
 220
 221         if (pdata && pdata->resume) {
 222                 rc = pdata->resume(dev);
 223 @@ -317,8 +383,7 @@ static int ahci_resume(struct device *dev)
 224         return 0;
 225
 226  disable_unprepare_clk:
 227 -       if (!IS_ERR(hpriv->clk))
 228 -               clk_disable_unprepare(hpriv->clk);
 229 +       ahci_disable_clks(hpriv);
 230
 231         return rc;
 232  }
 233 diff --git a/include/linux/ahci_platform.h b/include/linux/ahci_platform.h
 234 index 73a2500..769d065 100644
 235 --- a/include/linux/ahci_platform.h
 236 +++ b/include/linux/ahci_platform.h
 237 @@ -19,6 +19,7 @@
 238
 239  struct device;
 240  struct ata_port_info;
 241 +struct ahci_host_priv;
 242
 243  struct ahci_platform_data {
 244         int (*init)(struct device *dev, void __iomem *addr);
 245 @@ -30,4 +31,7 @@ struct ahci_platform_data {
 246         unsigned int mask_port_map;
 247  };
 248
 249 +int ahci_platform_enable_clks(struct ahci_host_priv *hpriv);
 250 +void ahci_platform_disable_clks(struct ahci_host_priv *hpriv);
 251 +
 252  #endif /* _AHCI_PLATFORM_H */
 253 --
 254 1.8.5.5
 255