target/linux/ipq806x/patches/0110-ahci-platform-Add-support-for-devices-with-more-then.patch

   1 From b7ad421c184b827806c7f65be3a980cfc855b589 Mon Sep 17 00:00:00 2001
   2 From: Hans de Goede <hdegoede@redhat.com>
   3 Date: Sat, 22 Feb 2014 16:53:31 +0100
   4 Subject: [PATCH 110/182] ahci-platform: Add support for devices with more
   5  then 1 clock
   6
   7 The allwinner-sun4i AHCI controller needs 2 clocks to be enabled and the
   8 imx AHCI controller needs 3 clocks to be enabled.
   9
  10 tj: Minor comment formatting updates.
  11
  12 Signed-off-by: Hans de Goede <hdegoede@redhat.com>
  13 Signed-off-by: Tejun Heo <tj@kernel.org>
  14 ---
  15  .../devicetree/bindings/ata/ahci-platform.txt      |    1 +
  16  drivers/ata/ahci.h                                 |    3 +-
  17  drivers/ata/ahci_platform.c                        |  113 +++++++++++++++-----
  18  include/linux/ahci_platform.h                      |    4 +
  19  4 files changed, 93 insertions(+), 28 deletions(-)
  20
  21 --- a/Documentation/devicetree/bindings/ata/ahci-platform.txt
  22 +++ b/Documentation/devicetree/bindings/ata/ahci-platform.txt
  23 @@ -10,6 +10,7 @@ Required properties:
  24
  25  Optional properties:
  26  - dma-coherent      : Present if dma operations are coherent
  27 +- clocks            : a list of phandle + clock specifier pairs
  28
  29  Example:
  30          sata@ffe08000 {
  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 @@ -322,7 +323,7 @@ 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 --- a/drivers/ata/ahci_platform.c
  51 +++ b/drivers/ata/ahci_platform.c
  52 @@ -87,6 +87,60 @@ static struct scsi_host_template ahci_pl
  53         AHCI_SHT("ahci_platform"),
  54  };
  55
  56 +/**
  57 + * ahci_platform_enable_clks - Enable platform clocks
  58 + * @hpriv: host private area to store config values
  59 + *
  60 + * This function enables all the clks found in hpriv->clks, starting at
  61 + * index 0. If any clk fails to enable it disables all the clks already
  62 + * enabled in reverse order, and then returns an error.
  63 + *
  64 + * RETURNS:
  65 + * 0 on success otherwise a negative error code
  66 + */
  67 +int ahci_platform_enable_clks(struct ahci_host_priv *hpriv)
  68 +{
  69 +       int c, rc;
  70 +
  71 +       for (c = 0; c < AHCI_MAX_CLKS && hpriv->clks[c]; c++) {
  72 +               rc = clk_prepare_enable(hpriv->clks[c]);
  73 +               if (rc)
  74 +                       goto disable_unprepare_clk;
  75 +       }
  76 +       return 0;
  77 +
  78 +disable_unprepare_clk:
  79 +       while (--c >= 0)
  80 +               clk_disable_unprepare(hpriv->clks[c]);
  81 +       return rc;
  82 +}
  83 +EXPORT_SYMBOL_GPL(ahci_platform_enable_clks);
  84 +
  85 +/**
  86 + * ahci_platform_disable_clks - Disable platform clocks
  87 + * @hpriv: host private area to store config values
  88 + *
  89 + * This function disables all the clks found in hpriv->clks, in reverse
  90 + * order of ahci_platform_enable_clks (starting at the end of the array).
  91 + */
  92 +void ahci_platform_disable_clks(struct ahci_host_priv *hpriv)
  93 +{
  94 +       int c;
  95 +
  96 +       for (c = AHCI_MAX_CLKS - 1; c >= 0; c--)
  97 +               if (hpriv->clks[c])
  98 +                       clk_disable_unprepare(hpriv->clks[c]);
  99 +}
 100 +EXPORT_SYMBOL_GPL(ahci_platform_disable_clks);
 101 +
 102 +static void ahci_put_clks(struct ahci_host_priv *hpriv)
 103 +{
 104 +       int c;
 105 +
 106 +       for (c = 0; c < AHCI_MAX_CLKS && hpriv->clks[c]; c++)
 107 +               clk_put(hpriv->clks[c]);
 108 +}
 109 +
 110  static int ahci_probe(struct platform_device *pdev)
 111  {
 112         struct device *dev = &pdev->dev;
 113 @@ -97,6 +151,7 @@ static int ahci_probe(struct platform_de
 114         struct ahci_host_priv *hpriv;
 115         struct ata_host *host;
 116         struct resource *mem;
 117 +       struct clk *clk;
 118         int irq;
 119         int n_ports;
 120         int i;
 121 @@ -131,17 +186,31 @@ static int ahci_probe(struct platform_de
 122                 return -ENOMEM;
 123         }
 124
 125 -       hpriv->clk = clk_get(dev, NULL);
 126 -       if (IS_ERR(hpriv->clk)) {
 127 -               dev_err(dev, "can't get clock\n");
 128 -       } else {
 129 -               rc = clk_prepare_enable(hpriv->clk);
 130 -               if (rc) {
 131 -                       dev_err(dev, "clock prepare enable failed");
 132 -                       goto free_clk;
 133 +       for (i = 0; i < AHCI_MAX_CLKS; i++) {
 134 +               /*
 135 +                * For now we must use clk_get(dev, NULL) for the first clock,
 136 +                * because some platforms (da850, spear13xx) are not yet
 137 +                * converted to use devicetree for clocks.  For new platforms
 138 +                * this is equivalent to of_clk_get(dev->of_node, 0).
 139 +                */
 140 +               if (i == 0)
 141 +                       clk = clk_get(dev, NULL);
 142 +               else
 143 +                       clk = of_clk_get(dev->of_node, i);
 144 +
 145 +               if (IS_ERR(clk)) {
 146 +                       rc = PTR_ERR(clk);
 147 +                       if (rc == -EPROBE_DEFER)
 148 +                               goto free_clk;
 149 +                       break;
 150                 }
 151 +               hpriv->clks[i] = clk;
 152         }
 153
 154 +       rc = ahci_enable_clks(dev, hpriv);
 155 +       if (rc)
 156 +               goto free_clk;
 157 +
 158         /*
 159          * Some platforms might need to prepare for mmio region access,
 160          * which could be done in the following init call. So, the mmio
 161 @@ -222,11 +291,9 @@ pdata_exit:
 162         if (pdata && pdata->exit)
 163                 pdata->exit(dev);
 164  disable_unprepare_clk:
 165 -       if (!IS_ERR(hpriv->clk))
 166 -               clk_disable_unprepare(hpriv->clk);
 167 +       ahci_disable_clks(hpriv);
 168  free_clk:
 169 -       if (!IS_ERR(hpriv->clk))
 170 -               clk_put(hpriv->clk);
 171 +       ahci_put_clks(hpriv);
 172         return rc;
 173  }
 174
 175 @@ -239,10 +306,8 @@ static void ahci_host_stop(struct ata_ho
 176         if (pdata && pdata->exit)
 177                 pdata->exit(dev);
 178
 179 -       if (!IS_ERR(hpriv->clk)) {
 180 -               clk_disable_unprepare(hpriv->clk);
 181 -               clk_put(hpriv->clk);
 182 -       }
 183 +       ahci_disable_clks(hpriv);
 184 +       ahci_put_clks(hpriv);
 185  }
 186
 187  #ifdef CONFIG_PM_SLEEP
 188 @@ -277,8 +342,7 @@ static int ahci_suspend(struct device *d
 189         if (pdata && pdata->suspend)
 190                 return pdata->suspend(dev);
 191
 192 -       if (!IS_ERR(hpriv->clk))
 193 -               clk_disable_unprepare(hpriv->clk);
 194 +       ahci_disable_clks(hpriv);
 195
 196         return 0;
 197  }
 198 @@ -290,13 +354,9 @@ static int ahci_resume(struct device *de
 199         struct ahci_host_priv *hpriv = host->private_data;
 200         int rc;
 201
 202 -       if (!IS_ERR(hpriv->clk)) {
 203 -               rc = clk_prepare_enable(hpriv->clk);
 204 -               if (rc) {
 205 -                       dev_err(dev, "clock prepare enable failed");
 206 -                       return rc;
 207 -               }
 208 -       }
 209 +       rc = ahci_enable_clks(dev, hpriv);
 210 +       if (rc)
 211 +               return rc;
 212
 213         if (pdata && pdata->resume) {
 214                 rc = pdata->resume(dev);
 215 @@ -317,8 +377,7 @@ static int ahci_resume(struct device *de
 216         return 0;
 217
 218  disable_unprepare_clk:
 219 -       if (!IS_ERR(hpriv->clk))
 220 -               clk_disable_unprepare(hpriv->clk);
 221 +       ahci_disable_clks(hpriv);
 222
 223         return rc;
 224  }
 225 --- a/include/linux/ahci_platform.h
 226 +++ b/include/linux/ahci_platform.h
 227 @@ -19,6 +19,7 @@
 228
 229  struct device;
 230  struct ata_port_info;
 231 +struct ahci_host_priv;
 232
 233  struct ahci_platform_data {
 234         int (*init)(struct device *dev, void __iomem *addr);
 235 @@ -30,4 +31,7 @@ struct ahci_platform_data {
 236         unsigned int mask_port_map;
 237  };
 238
 239 +int ahci_platform_enable_clks(struct ahci_host_priv *hpriv);
 240 +void ahci_platform_disable_clks(struct ahci_host_priv *hpriv);
 241 +
 242  #endif /* _AHCI_PLATFORM_H */