[U-Boot] Fwd: [PATCH 1/1] gpio: pca953x: Fix support chips with 24 GPIOs

[Максим Паймушкин]

---------- Переадресованное сообщение ----------
От: "Maxim Paymushkin" <maxim.paymushkin at gmail.com>
Дата: 15 июл. 2017 г. 19:12
Тема: [PATCH 1/1] gpio: pca953x: Fix support chips with 24 GPIOs
Кому: <u-boot-patches at bugs.denx.de>
Копия: "Maxim Paymushkin" <maxim.paymushkin at gmail.com>

A bug in the pca953x driver prevents correct detection the chips
with 24 GPIOs.
Generalized function of reading register for all implemented chips.

This patch fixes the reading behaviour.
---
 drivers/gpio/pca953x_gpio.c | 20 +++++++++-----------
 1 file changed, 9 insertions(+), 11 deletions(-)

diff --git a/drivers/gpio/pca953x_gpio.c b/drivers/gpio/pca953x_gpio.c
index 4962f25..7122774 100644
--- a/drivers/gpio/pca953x_gpio.c
+++ b/drivers/gpio/pca953x_gpio.c
@@ -35,6 +35,8 @@
 #define PCA953X_INVERT          2
 #define PCA953X_DIRECTION       3

+#define REG_ADDR_AI             0x80
+
 #define PCA_GPIO_MASK           0x00FF
 #define PCA_INT                 0x0100
 #define PCA953X_TYPE            0x1000
@@ -115,19 +117,15 @@ static int pca953x_read_single(struct udevice *dev,
int reg, u8 *val,
 static int pca953x_read_regs(struct udevice *dev, int reg, u8 *val)
 {
        struct pca953x_info *info = dev_get_platdata(dev);
+       int bank_shift = fls((info->gpio_count - 1) / BANK_SZ);
        int ret = 0;

-       if (info->gpio_count <= 8) {
-               ret = dm_i2c_read(dev, reg, val, 1);
-       } else if (info->gpio_count <= 16) {
-               ret = dm_i2c_read(dev, reg << 1, val, info->bank_count);
-       } else if (info->gpio_count == 40) {
-               /* Auto increment */
-               ret = dm_i2c_read(dev, (reg << 3) | 0x80, val,
info->bank_count);
-       } else {
-               dev_err(dev, "Unsupported now\n");
-               return -EINVAL;
-       }
+       reg <<= bank_shift;
+
+       if (info->gpio_count >= BANK_SZ * 3)
+               reg |= REG_ADDR_AI;
+
+       ret = dm_i2c_read(dev, reg, val, info->bank_count);

        return ret;
 }
--
2.7.4