pinctrl: ocelot: convert pinctrl to regmap

In order to allow external control via SPI, memory-mapped areas must be
changed to use the generic regmap interface. This is step 1, and is
followed by an implementation that allows a custom regmap.

Signed-off-by: Colin Foster <colin.foster@in-advantage.com>
Link: https://lore.kernel.org/r/20211119195928.2498441-4-colin.foster@in-advantage.com
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

diff --git a/drivers/pinctrl/pinctrl-ocelot.c b/drivers/pinctrl/pinctrl-ocelot.c
index d59d684..42aab9b 100644 (file)
--- a/drivers/pinctrl/pinctrl-ocelot.c
+++ b/drivers/pinctrl/pinctrl-ocelot.c
@@ -317,7 +317,7 @@ struct ocelot_pinctrl {
        struct pinctrl_dev *pctl;
        struct gpio_chip gpio_chip;
        struct regmap *map;
-       void __iomem *pincfg;
+       struct regmap *pincfg;
        struct pinctrl_desc *desc;
        struct ocelot_pmx_func func[FUNC_MAX];
        u8 stride;
@@ -1224,7 +1224,11 @@ static int ocelot_hw_get_value(struct ocelot_pinctrl *info,
        int ret = -EOPNOTSUPP;
 
        if (info->pincfg) {
-               u32 regcfg = readl(info->pincfg + (pin * sizeof(u32)));
+               u32 regcfg;
+
+               ret = regmap_read(info->pincfg, pin, &regcfg);
+               if (ret)
+                       return ret;
 
                ret = 0;
                switch (reg) {
@@ -1248,6 +1252,24 @@ static int ocelot_hw_get_value(struct ocelot_pinctrl *info,
        return ret;
 }
 
+static int ocelot_pincfg_clrsetbits(struct ocelot_pinctrl *info, u32 regaddr,
+                                   u32 clrbits, u32 setbits)
+{
+       u32 val;
+       int ret;
+
+       ret = regmap_read(info->pincfg, regaddr, &val);
+       if (ret)
+               return ret;
+
+       val &= ~clrbits;
+       val |= setbits;
+
+       ret = regmap_write(info->pincfg, regaddr, val);
+
+       return ret;
+}
+
 static int ocelot_hw_set_value(struct ocelot_pinctrl *info,
                               unsigned int pin,
                               unsigned int reg,
@@ -1256,21 +1278,23 @@ static int ocelot_hw_set_value(struct ocelot_pinctrl *info,
        int ret = -EOPNOTSUPP;
 
        if (info->pincfg) {
-               void __iomem *regaddr = info->pincfg + (pin * sizeof(u32));
 
                ret = 0;
                switch (reg) {
                case PINCONF_BIAS:
-                       ocelot_clrsetbits(regaddr, BIAS_BITS, val);
+                       ret = ocelot_pincfg_clrsetbits(info, pin, BIAS_BITS,
+                                                      val);
                        break;
 
                case PINCONF_SCHMITT:
-                       ocelot_clrsetbits(regaddr, SCHMITT_BIT, val);
+                       ret = ocelot_pincfg_clrsetbits(info, pin, SCHMITT_BIT,
+                                                      val);
                        break;
 
                case PINCONF_DRIVE_STRENGTH:
                        if (val <= 3)
-                               ocelot_clrsetbits(regaddr, DRIVE_BITS, val);
+                               ret = ocelot_pincfg_clrsetbits(info, pin,
+                                                              DRIVE_BITS, val);
                        else
                                ret = -EINVAL;
                        break;
@@ -1756,10 +1780,31 @@ static const struct of_device_id ocelot_pinctrl_of_match[] = {
        {},
 };
 
+static struct regmap *ocelot_pinctrl_create_pincfg(struct platform_device *pdev)
+{
+       void __iomem *base;
+
+       const struct regmap_config regmap_config = {
+               .reg_bits = 32,
+               .val_bits = 32,
+               .reg_stride = 4,
+               .max_register = 32,
+       };
+
+       base = devm_platform_ioremap_resource(pdev, 0);
+       if (IS_ERR(base)) {
+               dev_dbg(&pdev->dev, "Failed to ioremap config registers (no extended pinconf)\n");
+               return NULL;
+       }
+
+       return devm_regmap_init_mmio(&pdev->dev, base, &regmap_config);
+}
+
 static int ocelot_pinctrl_probe(struct platform_device *pdev)
 {
        struct device *dev = &pdev->dev;
        struct ocelot_pinctrl *info;
+       struct regmap *pincfg;
        void __iomem *base;
        int ret;
        struct regmap_config regmap_config = {
@@ -1793,11 +1838,11 @@ static int ocelot_pinctrl_probe(struct platform_device *pdev)
 
        /* Pinconf registers */
        if (info->desc->confops) {
-               base = devm_platform_ioremap_resource(pdev, 0);
-               if (IS_ERR(base))
-                       dev_dbg(dev, "Failed to ioremap config registers (no extended pinconf)\n");
+               pincfg = ocelot_pinctrl_create_pincfg(pdev);
+               if (IS_ERR(pincfg))
+                       dev_dbg(dev, "Failed to create pincfg regmap\n");
                else
-                       info->pincfg = base;
+                       info->pincfg = pincfg;
        }
 
        ret = ocelot_pinctrl_register(pdev, info);