usb: phy: samsung: Consolidate reference clock rate handling

This patch cleans up handling of reference clock rate in Samsung USB PHY
drivers. It is mostly a cosmetic change but improves error handling in
case of failing to get reference clock or invalid clock rate.

Signed-off-by: Tomasz Figa <t.figa@samsung.com>
Signed-off-by: Kyungmin Park <kyungmin.park@samsung.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

4 files changed, 86 insertions, 49 deletions

diff --git a/drivers/usb/phy/phy-samsung-usb.c b/drivers/usb/phy/phy-samsung-usb.c
index 62cdb7e13d97..c40ea321ae46 100644
--- a/drivers/usb/phy/phy-samsung-usb.c
+++ b/drivers/usb/phy/phy-samsung-usb.c
@@ -162,13 +162,76 @@ int samsung_usbphy_set_type(struct usb_phy *phy,
 }
 EXPORT_SYMBOL_GPL(samsung_usbphy_set_type);
 
+int samsung_usbphy_rate_to_clksel_64xx(struct samsung_usbphy *sphy,
+                                                        unsigned long rate)
+{
+        unsigned int clksel;
+
+        switch (rate) {
+        case 12 * MHZ:
+                clksel = PHYCLK_CLKSEL_12M;
+                break;
+        case 24 * MHZ:
+                clksel = PHYCLK_CLKSEL_24M;
+                break;
+        case 48 * MHZ:
+                clksel = PHYCLK_CLKSEL_48M;
+                break;
+        default:
+                dev_err(sphy->dev,
+                        "Invalid reference clock frequency: %lu\n", rate);
+                return -EINVAL;
+        }
+
+        return clksel;
+}
+EXPORT_SYMBOL_GPL(samsung_usbphy_rate_to_clksel_64xx);
+
+int samsung_usbphy_rate_to_clksel_4x12(struct samsung_usbphy *sphy,
+                                                        unsigned long rate)
+{
+        unsigned int clksel;
+
+        switch (rate) {
+        case 9600 * KHZ:
+                clksel = FSEL_CLKSEL_9600K;
+                break;
+        case 10 * MHZ:
+                clksel = FSEL_CLKSEL_10M;
+                break;
+        case 12 * MHZ:
+                clksel = FSEL_CLKSEL_12M;
+                break;
+        case 19200 * KHZ:
+                clksel = FSEL_CLKSEL_19200K;
+                break;
+        case 20 * MHZ:
+                clksel = FSEL_CLKSEL_20M;
+                break;
+        case 24 * MHZ:
+                clksel = FSEL_CLKSEL_24M;
+                break;
+        case 50 * MHZ:
+                clksel = FSEL_CLKSEL_50M;
+                break;
+        default:
+                dev_err(sphy->dev,
+                        "Invalid reference clock frequency: %lu\n", rate);
+                return -EINVAL;
+        }
+
+        return clksel;
+}
+EXPORT_SYMBOL_GPL(samsung_usbphy_rate_to_clksel_4x12);
+
 /*
  * Returns reference clock frequency selection value
  */
 int samsung_usbphy_get_refclk_freq(struct samsung_usbphy *sphy)
 {
         struct clk *ref_clk;
-        int refclk_freq = 0;
+        unsigned long rate;
+        int refclk_freq;
 
         /*
          * In exynos5250 USB host and device PHY use
@@ -183,52 +246,9 @@ int samsung_usbphy_get_refclk_freq(struct samsung_usbphy *sphy)
                 return PTR_ERR(ref_clk);
         }
 
-        if (sphy->drv_data->cpu_type == TYPE_EXYNOS5250) {
-                /* set clock frequency for PLL */
-                switch (clk_get_rate(ref_clk)) {
-                case 9600 * KHZ:
-                        refclk_freq = FSEL_CLKSEL_9600K;
-                        break;
-                case 10 * MHZ:
-                        refclk_freq = FSEL_CLKSEL_10M;
-                        break;
-                case 12 * MHZ:
-                        refclk_freq = FSEL_CLKSEL_12M;
-                        break;
-                case 19200 * KHZ:
-                        refclk_freq = FSEL_CLKSEL_19200K;
-                        break;
-                case 20 * MHZ:
-                        refclk_freq = FSEL_CLKSEL_20M;
-                        break;
-                case 50 * MHZ:
-                        refclk_freq = FSEL_CLKSEL_50M;
-                        break;
-                case 24 * MHZ:
-                default:
-                        /* default reference clock */
-                        refclk_freq = FSEL_CLKSEL_24M;
-                        break;
-                }
-        } else {
-                switch (clk_get_rate(ref_clk)) {
-                case 12 * MHZ:
-                        refclk_freq = PHYCLK_CLKSEL_12M;
-                        break;
-                case 24 * MHZ:
-                        refclk_freq = PHYCLK_CLKSEL_24M;
-                        break;
-                case 48 * MHZ:
-                        refclk_freq = PHYCLK_CLKSEL_48M;
-                        break;
-                default:
-                        if (sphy->drv_data->cpu_type == TYPE_S3C64XX)
-                                refclk_freq = PHYCLK_CLKSEL_48M;
-                        else
-                                refclk_freq = PHYCLK_CLKSEL_24M;
-                        break;
-                }
-        }
+        rate = clk_get_rate(ref_clk);
+        refclk_freq = sphy->drv_data->rate_to_clksel(sphy, rate);
+
         clk_put(ref_clk);
 
         return refclk_freq;
diff --git a/drivers/usb/phy/phy-samsung-usb.h b/drivers/usb/phy/phy-samsung-usb.h
index 70a9cae5e37f..0336f6b02bc4 100644
--- a/drivers/usb/phy/phy-samsung-usb.h
+++ b/drivers/usb/phy/phy-samsung-usb.h
@@ -244,6 +244,8 @@ enum samsung_cpu_type {
         TYPE_EXYNOS5250,
 };
 
+struct samsung_usbphy;
+
 /*
  * struct samsung_usbphy_drvdata - driver data for various SoC variants
  * @cpu_type: machine identifier
@@ -268,6 +270,7 @@ struct samsung_usbphy_drvdata {
         int hostphy_en_mask;
         u32 devphy_reg_offset;
         u32 hostphy_reg_offset;
+        int (*rate_to_clksel)(struct samsung_usbphy *, unsigned long);
 };
 
 /*
@@ -325,3 +328,7 @@ extern void samsung_usbphy_cfg_sel(struct samsung_usbphy *sphy);
 extern int samsung_usbphy_set_type(struct usb_phy *phy,
                                         enum samsung_usb_phy_type phy_type);
 extern int samsung_usbphy_get_refclk_freq(struct samsung_usbphy *sphy);
+extern int samsung_usbphy_rate_to_clksel_64xx(struct samsung_usbphy *sphy,
+                                                        unsigned long rate);
+extern int samsung_usbphy_rate_to_clksel_4x12(struct samsung_usbphy *sphy,
+                                                        unsigned long rate);
diff --git a/drivers/usb/phy/phy-samsung-usb2.c b/drivers/usb/phy/phy-samsung-usb2.c
index 9d5e273abcc7..be6031d50a6d 100644
--- a/drivers/usb/phy/phy-samsung-usb2.c
+++ b/drivers/usb/phy/phy-samsung-usb2.c
@@ -408,7 +408,10 @@ static int samsung_usb2phy_probe(struct platform_device *pdev)
         sphy->phy.label         = "samsung-usb2phy";
         sphy->phy.init          = samsung_usb2phy_init;
         sphy->phy.shutdown      = samsung_usb2phy_shutdown;
-        sphy->ref_clk_freq      = samsung_usbphy_get_refclk_freq(sphy);
+
+        sphy->ref_clk_freq = samsung_usbphy_get_refclk_freq(sphy);
+        if (sphy->ref_clk_freq < 0)
+                return -EINVAL;
 
         sphy->phy.otg           = otg;
         sphy->phy.otg->phy      = &sphy->phy;
@@ -438,18 +441,21 @@ static int samsung_usb2phy_remove(struct platform_device *pdev)
 static const struct samsung_usbphy_drvdata usb2phy_s3c64xx = {
         .cpu_type               = TYPE_S3C64XX,
         .devphy_en_mask         = S3C64XX_USBPHY_ENABLE,
+        .rate_to_clksel         = samsung_usbphy_rate_to_clksel_64xx,
 };
 
 static const struct samsung_usbphy_drvdata usb2phy_exynos4 = {
         .cpu_type               = TYPE_EXYNOS4210,
         .devphy_en_mask         = EXYNOS_USBPHY_ENABLE,
         .hostphy_en_mask        = EXYNOS_USBPHY_ENABLE,
+        .rate_to_clksel         = samsung_usbphy_rate_to_clksel_64xx,
 };
 
 static struct samsung_usbphy_drvdata usb2phy_exynos5 = {
         .cpu_type               = TYPE_EXYNOS5250,
         .hostphy_en_mask        = EXYNOS_USBPHY_ENABLE,
         .hostphy_reg_offset     = EXYNOS_USBHOST_PHY_CTRL_OFFSET,
+        .rate_to_clksel         = samsung_usbphy_rate_to_clksel_4x12,
 };
 
 #ifdef CONFIG_OF
diff --git a/drivers/usb/phy/phy-samsung-usb3.c b/drivers/usb/phy/phy-samsung-usb3.c
index 5a9efcbcb532..ec44b35fb24a 100644
--- a/drivers/usb/phy/phy-samsung-usb3.c
+++ b/drivers/usb/phy/phy-samsung-usb3.c
@@ -274,7 +274,10 @@ static int samsung_usb3phy_probe(struct platform_device *pdev)
         sphy->phy.init          = samsung_usb3phy_init;
         sphy->phy.shutdown      = samsung_usb3phy_shutdown;
         sphy->drv_data          = samsung_usbphy_get_driver_data(pdev);
-        sphy->ref_clk_freq      = samsung_usbphy_get_refclk_freq(sphy);
+
+        sphy->ref_clk_freq = samsung_usbphy_get_refclk_freq(sphy);
+        if (sphy->ref_clk_freq < 0)
+                return -EINVAL;
 
         spin_lock_init(&sphy->lock);
 
@@ -300,6 +303,7 @@ static int samsung_usb3phy_remove(struct platform_device *pdev)
 static struct samsung_usbphy_drvdata usb3phy_exynos5 = {
         .cpu_type               = TYPE_EXYNOS5250,
         .devphy_en_mask         = EXYNOS_USBPHY_ENABLE,
+        .rate_to_clksel         = samsung_usbphy_rate_to_clksel_4x12,
 };
 
 #ifdef CONFIG_OF