[PATCH 07/11] pinctrl: single: use function pointer for register access

[Dario Binacchi]

The patch allows you to call the read/write functions set during probing
without having to check the type of access at runtime. It also adds
functions for 8-bit registers access.

Signed-off-by: Dario Binacchi <dario...@libero.it>
---

 drivers/pinctrl/pinctrl-single.c | 98 ++++++++++++++++++++++++--------
 1 file changed, 73 insertions(+), 25 deletions(-)

diff --git a/drivers/pinctrl/pinctrl-single.c b/drivers/pinctrl/pinctrl-single.c
index 09bb883041..eb69e53096 100644
--- a/drivers/pinctrl/pinctrl-single.c
+++ b/drivers/pinctrl/pinctrl-single.c
@@ -26,6 +26,16 @@ struct single_pdata {
        bool bits_per_mux;
 };
 
+/**
+ * struct single_priv - private data
+ * @read: function to read from a configuration register
+ * @write: function to write to a configuration register
+ */
+struct single_priv {
+       unsigned int (*read)(fdt_addr_t reg);
+       void (*write)(unsigned int val, fdt_addr_t reg);
+};
+
 /**
  * struct single_fdt_pin_cfg - pin configuration
  *
@@ -56,6 +66,36 @@ struct single_fdt_bits_cfg {
        fdt32_t mask;
 };
 
+static unsigned int single_readb(fdt_addr_t reg)
+{
+       return readb(reg);
+}
+
+static unsigned int single_readw(fdt_addr_t reg)
+{
+       return readw(reg);
+}
+
+static unsigned int single_readl(fdt_addr_t reg)
+{
+       return readl(reg);
+}
+
+static void single_writeb(unsigned int val, fdt_addr_t reg)
+{
+       writeb(val, reg);
+}
+
+static void single_writew(unsigned int val, fdt_addr_t reg)
+{
+       writew(val, reg);
+}
+
+static void single_writel(unsigned int val, fdt_addr_t reg)
+{
+       writel(val, reg);
+}
+
 /**
  * single_configure_pins() - Configure pins based on FDT data
  *
@@ -75,6 +115,7 @@ static int single_configure_pins(struct udevice *dev,
                                 int size)
 {
        struct single_pdata *pdata = dev_get_plat(dev);
+       struct single_priv *priv = dev_get_priv(dev);
        int n, count = size / sizeof(struct single_fdt_pin_cfg);
        phys_addr_t reg;
        u32 offset, val;
@@ -93,19 +134,9 @@ static int single_configure_pins(struct udevice *dev,
 
                reg = pdata->base + offset;
                val = fdt32_to_cpu(pins->val) & pdata->mask;
-               switch (pdata->width) {
-               case 16:
-                       writew((readw(reg) & ~pdata->mask) | val, reg);
-                       break;
-               case 32:
-                       writel((readl(reg) & ~pdata->mask) | val, reg);
-                       break;
-               default:
-                       dev_warn(dev, "unsupported register width %i\n",
-                                pdata->width);
-                       continue;
-               }
+               priv->write((priv->read(reg) & ~pdata->mask) | val, reg);
                dev_dbg(dev, "  reg/val %pa/0x%08x\n", &reg, val);
+
        }
        return 0;
 }
@@ -115,6 +146,7 @@ static int single_configure_bits(struct udevice *dev,
                                 int size)
 {
        struct single_pdata *pdata = dev_get_plat(dev);
+       struct single_priv *priv = dev_get_priv(dev);
        int n, count = size / sizeof(struct single_fdt_bits_cfg);
        phys_addr_t reg;
        u32 offset, val, mask;
@@ -131,19 +163,7 @@ static int single_configure_bits(struct udevice *dev,
 
                mask = fdt32_to_cpu(pins->mask);
                val = fdt32_to_cpu(pins->val) & mask;
-
-               switch (pdata->width) {
-               case 16:
-                       writew((readw(reg) & ~mask) | val, reg);
-                       break;
-               case 32:
-                       writel((readl(reg) & ~mask) | val, reg);
-                       break;
-               default:
-                       dev_warn(dev, "unsupported register width %i\n",
-                                pdata->width);
-                       continue;
-               }
+               priv->write((priv->read(reg) & ~mask) | val, reg);
                dev_dbg(dev, "  reg/val %pa/0x%08x\n", &reg, val);
        }
        return 0;
@@ -183,6 +203,32 @@ static int single_set_state(struct udevice *dev,
        return len;
 }
 
+static int single_probe(struct udevice *dev)
+{
+       struct single_pdata *pdata = dev_get_plat(dev);
+       struct single_priv *priv = dev_get_priv(dev);
+
+       switch (pdata->width) {
+       case 8:
+               priv->read = single_readb;
+               priv->write = single_writeb;
+               break;
+       case 16:
+               priv->read = single_readw;
+               priv->write = single_writew;
+               break;
+       case 32:
+               priv->read = single_readl;
+               priv->write = single_writel;
+               break;
+       default:
+               dev_err(dev, "wrong register width\n");
+               return -EINVAL;
+       }
+
+       return 0;
+}
+
 static int single_of_to_plat(struct udevice *dev)
 {
        fdt_addr_t addr;
@@ -232,5 +278,7 @@ U_BOOT_DRIVER(single_pinctrl) = {
        .of_match = single_pinctrl_match,
        .ops = &single_pinctrl_ops,
        .plat_auto      = sizeof(struct single_pdata),
+       .priv_auto = sizeof(struct single_priv),
        .of_to_plat = single_of_to_plat,
+       .probe = single_probe,
 };
-- 
2.17.1