gpio: kempld: Add support for PLD version >= 2.8

Starting with version 2.8 there is a dedicated register to configure
the output level. Read the PLD version in the probe and select the
correct register to use for the set operations.

Signed-off-by: Alban Bedel <alban.bedel@lht.dlh.de>
Link: https://patch.msgid.link/20260311143120.2179347-3-alban.bedel@lht.dlh.de
Signed-off-by: Bartosz Golaszewski <bartosz.golaszewski@oss.qualcomm.com>

diff --git a/drivers/gpio/gpio-kempld.c b/drivers/gpio/gpio-kempld.c
index 532e4000879aba5ac475b62bc5ad424279e9726c..2263de77d40e962b266120126e4133d382ef0a3c 100644 (file)
--- a/drivers/gpio/gpio-kempld.c
+++ b/drivers/gpio/gpio-kempld.c
@@ -25,6 +25,7 @@
 struct kempld_gpio_data {
        struct gpio_chip                chip;
        struct kempld_device_data       *pld;
+       u8                              out_lvl_reg;
 };
 
 /*
@@ -71,7 +72,7 @@ static int kempld_gpio_set(struct gpio_chip *chip, unsigned int offset,
        struct kempld_device_data *pld = gpio->pld;
 
        kempld_get_mutex(pld);
-       kempld_gpio_bitop(pld, KEMPLD_GPIO_LVL, offset, value);
+       kempld_gpio_bitop(pld, gpio->out_lvl_reg, offset, value);
        kempld_release_mutex(pld);
 
        return 0;
@@ -96,7 +97,7 @@ static int kempld_gpio_direction_output(struct gpio_chip *chip, unsigned offset,
        struct kempld_device_data *pld = gpio->pld;
 
        kempld_get_mutex(pld);
-       kempld_gpio_bitop(pld, KEMPLD_GPIO_LVL, offset, value);
+       kempld_gpio_bitop(pld, gpio->out_lvl_reg, offset, value);
        kempld_gpio_bitop(pld, KEMPLD_GPIO_DIR, offset, 1);
        kempld_release_mutex(pld);
 
@@ -153,6 +154,15 @@ static int kempld_gpio_probe(struct platform_device *pdev)
        if (!gpio)
                return -ENOMEM;
 
+       /* Starting with version 2.8 there is a dedicated register for the
+        * output state, earlier versions share the register used to read
+        * the line level.
+        */
+       if (pld->info.spec_major > 2 || pld->info.spec_minor >= 8)
+               gpio->out_lvl_reg = KEMPLD_GPIO_OUT_LVL;
+       else
+               gpio->out_lvl_reg = KEMPLD_GPIO_LVL;
+
        gpio->pld = pld;
 
        platform_set_drvdata(pdev, gpio);