ata/ahci_platform: Add clock framework support

On many architectures, drivers are supposed to prepare/unprepare &
enable/disable functional clock of device. This patch adds clock support for
ahci_platform.

Signed-off-by: Viresh Kumar <viresh.kumar@linaro.com>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>

diff --git a/drivers/ata/ahci.h b/drivers/ata/ahci.h
index 6441cbecfa1d79d8083db8d47825c47f31e5de78..9be471200a07657f1f655ea31d805e0d6223c24b 100644 (file)
--- a/drivers/ata/ahci.h
+++ b/drivers/ata/ahci.h
@@ -35,6 +35,7 @@
 #ifndef _AHCI_H
 #define _AHCI_H
 
+#include <linux/clk.h>
 #include <linux/libata.h>
 
 /* Enclosure Management Control */
@@ -316,6 +317,7 @@ struct ahci_host_priv {
        u32                     em_loc; /* enclosure management location */
        u32                     em_buf_sz;      /* EM buffer size in byte */
        u32                     em_msg_type;    /* EM message type */
+       struct clk              *clk;           /* Only for platforms supporting clk */
 };
 
 extern int ahci_ignore_sss;

diff --git a/drivers/ata/ahci_platform.c b/drivers/ata/ahci_platform.c
index dc187c746649a199dffaa67feedcd7ca1bbc709f..b1ae48054dc5773eab42917d5e9d10f9764602ae 100644 (file)
--- a/drivers/ata/ahci_platform.c
+++ b/drivers/ata/ahci_platform.c
@@ -12,6 +12,7 @@
  * any later version.
  */
 
+#include <linux/clk.h>
 #include <linux/kernel.h>
 #include <linux/gfp.h>
 #include <linux/module.h>
@@ -118,6 +119,17 @@ static int __init ahci_probe(struct platform_device *pdev)
                return -ENOMEM;
        }
 
+       hpriv->clk = clk_get(dev, NULL);
+       if (IS_ERR(hpriv->clk)) {
+               dev_err(dev, "can't get clock\n");
+       } else {
+               rc = clk_prepare_enable(hpriv->clk);
+               if (rc) {
+                       dev_err(dev, "clock prepare enable failed");
+                       goto free_clk;
+               }
+       }
+
        /*
         * Some platforms might need to prepare for mmio region access,
         * which could be done in the following init call. So, the mmio
@@ -127,7 +139,7 @@ static int __init ahci_probe(struct platform_device *pdev)
        if (pdata && pdata->init) {
                rc = pdata->init(dev, hpriv->mmio);
                if (rc)
-                       return rc;
+                       goto disable_unprepare_clk;
        }
 
        ahci_save_initial_config(dev, hpriv,
@@ -153,7 +165,7 @@ static int __init ahci_probe(struct platform_device *pdev)
        host = ata_host_alloc_pinfo(dev, ppi, n_ports);
        if (!host) {
                rc = -ENOMEM;
-               goto err0;
+               goto pdata_exit;
        }
 
        host->private_data = hpriv;
@@ -183,7 +195,7 @@ static int __init ahci_probe(struct platform_device *pdev)
 
        rc = ahci_reset_controller(host);
        if (rc)
-               goto err0;
+               goto pdata_exit;
 
        ahci_init_controller(host);
        ahci_print_info(host, "platform");
@@ -191,12 +203,18 @@ static int __init ahci_probe(struct platform_device *pdev)
        rc = ata_host_activate(host, irq, ahci_interrupt, IRQF_SHARED,
                               &ahci_platform_sht);
        if (rc)
-               goto err0;
+               goto pdata_exit;
 
        return 0;
-err0:
+pdata_exit:
        if (pdata && pdata->exit)
                pdata->exit(dev);
+disable_unprepare_clk:
+       if (!IS_ERR(hpriv->clk))
+               clk_disable_unprepare(hpriv->clk);
+free_clk:
+       if (!IS_ERR(hpriv->clk))
+               clk_put(hpriv->clk);
        return rc;
 }
 
@@ -205,12 +223,18 @@ static int __devexit ahci_remove(struct platform_device *pdev)
        struct device *dev = &pdev->dev;
        struct ahci_platform_data *pdata = dev_get_platdata(dev);
        struct ata_host *host = dev_get_drvdata(dev);
+       struct ahci_host_priv *hpriv = host->private_data;
 
        ata_host_detach(host);
 
        if (pdata && pdata->exit)
                pdata->exit(dev);
 
+       if (!IS_ERR(hpriv->clk)) {
+               clk_disable_unprepare(hpriv->clk);
+               clk_put(hpriv->clk);
+       }
+
        return 0;
 }
 
@@ -245,6 +269,10 @@ static int ahci_suspend(struct device *dev)
 
        if (pdata && pdata->suspend)
                return pdata->suspend(dev);
+
+       if (!IS_ERR(hpriv->clk))
+               clk_disable_unprepare(hpriv->clk);
+
        return 0;
 }
 
@@ -252,18 +280,27 @@ static int ahci_resume(struct device *dev)
 {
        struct ahci_platform_data *pdata = dev_get_platdata(dev);
        struct ata_host *host = dev_get_drvdata(dev);
+       struct ahci_host_priv *hpriv = host->private_data;
        int rc;
 
+       if (!IS_ERR(hpriv->clk)) {
+               rc = clk_prepare_enable(hpriv->clk);
+               if (rc) {
+                       dev_err(dev, "clock prepare enable failed");
+                       return rc;
+               }
+       }
+
        if (pdata && pdata->resume) {
                rc = pdata->resume(dev);
                if (rc)
-                       return rc;
+                       goto disable_unprepare_clk;
        }
 
        if (dev->power.power_state.event == PM_EVENT_SUSPEND) {
                rc = ahci_reset_controller(host);
                if (rc)
-                       return rc;
+                       goto disable_unprepare_clk;
 
                ahci_init_controller(host);
        }
@@ -271,6 +308,12 @@ static int ahci_resume(struct device *dev)
        ata_host_resume(host);
 
        return 0;
+
+disable_unprepare_clk:
+       if (!IS_ERR(hpriv->clk))
+               clk_disable_unprepare(hpriv->clk);
+
+       return rc;
 }
 #endif