pinctrl: mediatek: Check gpio pin number and use binary search in mtk_hw_pin_field_lo...

1. Check if gpio pin number is in valid range to prevent from get invalid
   pointer 'desc' in the following code:
	desc = (const struct mtk_pin_desc *)&hw->soc->pins[gpio];

2. Improve  mtk_hw_pin_field_lookup()
2.1 Modify mtk_hw_pin_field_lookup() to use binary search for accelerating
     search.
2.2 Correct message after the following check fail:
    if (hw->soc->reg_cal && hw->soc->reg_cal[field].range) {
		rc = &hw->soc->reg_cal[field];
    The original message is:
    	"Not support field %d for pin %d (%s)\n"
    However, the check is on soc chip level, not on pin level yet.
    So the message is corrected as:
    	"Not support field %d for this soc\n"

Signed-off-by: Light Hsieh <light.hsieh@mediatek.com>
Link: https://lore.kernel.org/r/1579675994-7001-1-git-send-email-light.hsieh@mediatek.com
Acked-by: Sean Wang <sean.wang@kernel.org>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

diff --git a/drivers/pinctrl/mediatek/pinctrl-mtk-common-v2.c b/drivers/pinctrl/mediatek/pinctrl-mtk-common-v2.c
index 20e1c89..d63e05e 100644 (file)
--- a/drivers/pinctrl/mediatek/pinctrl-mtk-common-v2.c
+++ b/drivers/pinctrl/mediatek/pinctrl-mtk-common-v2.c
@@ -68,32 +68,44 @@ static int mtk_hw_pin_field_lookup(struct mtk_pinctrl *hw,
 {
        const struct mtk_pin_field_calc *c, *e;
        const struct mtk_pin_reg_calc *rc;
+       int start = 0, end, check;
+       bool found = false;
        u32 bits;
 
        if (hw->soc->reg_cal && hw->soc->reg_cal[field].range) {
                rc = &hw->soc->reg_cal[field];
        } else {
                dev_dbg(hw->dev,
-                       "Not support field %d for pin %d (%s)\n",
-                       field, desc->number, desc->name);
+                       "Not support field %d for this soc\n", field);
                return -ENOTSUPP;
        }
 
+       end = rc->nranges - 1;
        c = rc->range;
        e = c + rc->nranges;
 
-       while (c < e) {
-               if (desc->number >= c->s_pin && desc->number <= c->e_pin)
+       while (start <= end) {
+               check = (start + end) >> 1;
+               if (desc->number >= rc->range[check].s_pin
+                && desc->number <= rc->range[check].e_pin) {
+                       found = true;
+                       break;
+               } else if (start == end)
                        break;
-               c++;
+               else if (desc->number < rc->range[check].s_pin)
+                       end = check - 1;
+               else
+                       start = check + 1;
        }
 
-       if (c >= e) {
+       if (!found) {
                dev_dbg(hw->dev, "Not support field %d for pin = %d (%s)\n",
                        field, desc->number, desc->name);
                return -ENOTSUPP;
        }
 
+       c = rc->range + check;
+
        if (c->i_base > hw->nbase - 1) {
                dev_err(hw->dev,
                        "Invalid base for field %d for pin = %d (%s)\n",
@@ -182,6 +194,9 @@ int mtk_hw_set_value(struct mtk_pinctrl *hw, const struct mtk_pin_desc *desc,
        if (err)
                return err;
 
+       if (value < 0 || value > pf.mask)
+               return -EINVAL;
+
        if (!pf.next)
                mtk_rmw(hw, pf.index, pf.offset, pf.mask << pf.bitpos,
                        (value & pf.mask) << pf.bitpos);

diff --git a/drivers/pinctrl/mediatek/pinctrl-paris.c b/drivers/pinctrl/mediatek/pinctrl-paris.c
index 923264d..3e13ae7 100644 (file)
--- a/drivers/pinctrl/mediatek/pinctrl-paris.c
+++ b/drivers/pinctrl/mediatek/pinctrl-paris.c
@@ -81,6 +81,8 @@ static int mtk_pinconf_get(struct pinctrl_dev *pctldev,
        int val, val2, err, reg, ret = 1;
        const struct mtk_pin_desc *desc;
 
+       if (pin >= hw->soc->npins)
+               return -EINVAL;
        desc = (const struct mtk_pin_desc *)&hw->soc->pins[pin];
 
        switch (param) {
@@ -206,6 +208,10 @@ static int mtk_pinconf_set(struct pinctrl_dev *pctldev, unsigned int pin,
        int err = 0;
        u32 reg;
 
+       if (pin >= hw->soc->npins) {
+               err = -EINVAL;
+               goto err;
+       }
        desc = (const struct mtk_pin_desc *)&hw->soc->pins[pin];
 
        switch ((u32)param) {
@@ -693,6 +699,9 @@ static int mtk_gpio_get_direction(struct gpio_chip *chip, unsigned int gpio)
        const struct mtk_pin_desc *desc;
        int value, err;
 
+       if (gpio > hw->soc->npins)
+               return -EINVAL;
+
        desc = (const struct mtk_pin_desc *)&hw->soc->pins[gpio];
 
        err = mtk_hw_get_value(hw, desc, PINCTRL_PIN_REG_DIR, &value);
@@ -708,6 +717,9 @@ static int mtk_gpio_get(struct gpio_chip *chip, unsigned int gpio)
        const struct mtk_pin_desc *desc;
        int value, err;
 
+       if (gpio > hw->soc->npins)
+               return -EINVAL;
+
        desc = (const struct mtk_pin_desc *)&hw->soc->pins[gpio];
 
        err = mtk_hw_get_value(hw, desc, PINCTRL_PIN_REG_DI, &value);
@@ -722,6 +734,9 @@ static void mtk_gpio_set(struct gpio_chip *chip, unsigned int gpio, int value)
        struct mtk_pinctrl *hw = gpiochip_get_data(chip);
        const struct mtk_pin_desc *desc;
 
+       if (gpio > hw->soc->npins)
+               return;
+
        desc = (const struct mtk_pin_desc *)&hw->soc->pins[gpio];
 
        mtk_hw_set_value(hw, desc, PINCTRL_PIN_REG_DO, !!value);
@@ -729,12 +744,22 @@ static void mtk_gpio_set(struct gpio_chip *chip, unsigned int gpio, int value)
 
 static int mtk_gpio_direction_input(struct gpio_chip *chip, unsigned int gpio)
 {
+       struct mtk_pinctrl *hw = gpiochip_get_data(chip);
+
+       if (gpio > hw->soc->npins)
+               return -EINVAL;
+
        return pinctrl_gpio_direction_input(chip->base + gpio);
 }
 
 static int mtk_gpio_direction_output(struct gpio_chip *chip, unsigned int gpio,
                                     int value)
 {
+       struct mtk_pinctrl *hw = gpiochip_get_data(chip);
+
+       if (gpio > hw->soc->npins)
+               return -EINVAL;
+
        mtk_gpio_set(chip, gpio, value);
 
        return pinctrl_gpio_direction_output(chip->base + gpio);