This patch changes the initialization sequence implemented in
pca953x_probe(), so as to simplify the retrieval of device tree
data when device trees are used. Incorporates the new
of_i2c_gpiochip_add() function to register the newly-added GPIOs.
Signed-off-by: Bill Gatliff <b...@billgatliff.com>
---
drivers/gpio/pca953x.c | 130 +++++++++++++++++++++--------------------------
1 files changed, 58 insertions(+), 72 deletions(-)
diff --git a/drivers/gpio/pca953x.c b/drivers/gpio/pca953x.c
index 9c70963..3a20e2f 100644
--- a/drivers/gpio/pca953x.c
+++ b/drivers/gpio/pca953x.c
@@ -3,6 +3,7 @@
*
* Copyright (C) 2005 Ben Gardner <bgard...@wabtec.com>
* Copyright (C) 2007 Marvell International Ltd.
+ * Copyright (C) 2010 Bill Gatliff <b...@billgatliff.com>
*
* Derived from drivers/i2c/chips/pca9539.c
*
@@ -53,13 +54,13 @@ static const struct i2c_device_id pca953x_id[] = {
MODULE_DEVICE_TABLE(i2c, pca953x_id);
struct pca953x_chip {
- unsigned gpio_start;
uint16_t reg_output;
uint16_t reg_direction;
+ uint16_t reg_invert;
struct gpio_chip *gpio_chip;
struct i2c_client *client;
- struct pca953x_platform_data *dyn_pdata;
+ struct pca953x_platform_data *pdata;
char **names;
#ifdef CONFIG_OF_GPIO
@@ -214,7 +215,6 @@ static void pca953x_setup_gpio(struct pca953x_chip *chip,
int gpios)
gc->set = pca953x_gpio_set_value;
gc->can_sleep = 1;
- gc->base = chip->gpio_start;
gc->ngpio = gpios;
gc->label = chip->client->name;
gc->dev = &chip->client->dev;
@@ -222,119 +222,107 @@ static void pca953x_setup_gpio(struct pca953x_chip
*chip, int gpios)
gc->names = chip->names;
}
-/*
- * Handlers for alternative sources of platform_data
- */
#ifdef CONFIG_OF_GPIO
-/*
- * Translate OpenFirmware node properties into platform_data
- */
-static struct pca953x_platform_data *
-pca953x_get_alt_pdata(struct i2c_client *client)
+static int __devinit pca953x_get_of_pdata(struct pca953x_chip *chip)
{
- struct pca953x_platform_data *pdata;
struct device_node *node;
const uint16_t *val;
- node = dev_archdata_get_node(&client->dev.archdata);
- if (node == NULL)
- return NULL;
+ node = dev_archdata_get_node(&chip->client->dev.archdata);
+ if (!node)
+ return -EINVAL;
- pdata = kzalloc(sizeof(struct pca953x_platform_data), GFP_KERNEL);
- if (pdata == NULL) {
- dev_err(&client->dev, "Unable to allocate platform_data\n");
- return NULL;
- }
-
- pdata->gpio_base = -1;
- val = of_get_property(node, "linux,gpio-base", NULL);
- if (val) {
- if (*val < 0)
- dev_warn(&client->dev,
- "invalid gpio-base in device tree\n");
- else
- pdata->gpio_base = *val;
- }
+ chip->gpio_chip->base = -1;
+ chip->i2c_gc.of_gc.gpio_cells = 2;
val = of_get_property(node, "polarity", NULL);
if (val)
- pdata->invert = *val;
+ chip->reg_invert = *val;
- return pdata;
+ return 0;
}
-#else
-static struct pca953x_platform_data *
-pca953x_get_alt_pdata(struct i2c_client *client)
+
+static int __devinit pca953x_gpiochip_add(struct pca953x_chip *chip)
{
- return NULL;
+ struct device_node *node;
+ node = dev_archdata_get_node(&chip->client->dev.archdata);
+ return of_i2c_gpiochip_add(node, &chip->i2c_gc);
}
#endif
+static int __devinit pca953x_get_pdata(struct pca953x_chip *chip)
+{
+ struct pca953x_platform_data *pdata;
+
+ pdata = dev_get_platdata(&chip->client->dev);
+ if (!pdata)
+ return -EINVAL;
+
+ chip->pdata = pdata;
+ chip->gpio_chip->base = pdata->gpio_base;
+ chip->reg_invert = pdata->invert;
+
+ return 0;
+}
+
static int __devinit pca953x_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
- struct pca953x_platform_data *pdata;
struct pca953x_chip *chip;
int ret;
chip = kzalloc(sizeof(struct pca953x_chip), GFP_KERNEL);
if (chip == NULL)
return -ENOMEM;
+ chip->client = client;
#ifdef CONFIG_OF_GPIO
chip->gpio_chip = &chip->i2c_gc.of_gc.gc;
+ if (!dev_get_platdata(&client->dev))
+ pca953x_get_of_pdata(chip);
#else
chip->gpio_chip = &chip->gc;
-#endif
-
- pdata = client->dev.platform_data;
- if (pdata == NULL) {
- pdata = pca953x_get_alt_pdata(client);
- /*
- * Unlike normal platform_data, this is allocated
- * dynamically and must be freed in the driver
- */
- chip->dyn_pdata = pdata;
- }
-
- if (pdata == NULL) {
- dev_dbg(&client->dev, "no platform data\n");
+ if (!client->dev.platform_data)
+ {
+ dev_err(&client->dev, "no platform data\n");
ret = -EINVAL;
goto out_failed;
}
+#endif
- chip->client = client;
-
- chip->gpio_start = pdata->gpio_base;
+ pca953x_setup_gpio(chip, id->driver_data);
- chip->names = pdata->names;
+ if (dev_get_platdata(&client->dev))
+ pca953x_get_pdata(chip);
- /* initialize cached registers from their original values.
- * we can't share this chip with another i2c master.
+ /*
+ * Note: we cache the values of some registers locally; this
+ * means that other i2c masters, if any, cannot share this
+ * chip with us!
*/
- pca953x_setup_gpio(chip, id->driver_data);
ret = pca953x_read_reg(chip, PCA953X_OUTPUT, &chip->reg_output);
if (ret)
goto out_failed;
-
ret = pca953x_read_reg(chip, PCA953X_DIRECTION, &chip->reg_direction);
if (ret)
goto out_failed;
-
- /* set platform specific polarity inversion */
- ret = pca953x_write_reg(chip, PCA953X_INVERT, pdata->invert);
+ ret = pca953x_write_reg(chip, PCA953X_INVERT, chip->reg_invert);
if (ret)
goto out_failed;
-
+#ifdef CONFIG_OF_GPIO
+ ret = pca953x_gpiochip_add(chip);
+#else
ret = gpiochip_add(chip->gpio_chip);
+#endif
if (ret)
goto out_failed;
- if (pdata->setup) {
- ret = pdata->setup(client, chip->gpio_chip->base,
- chip->gpio_chip->ngpio, pdata->context);
+ if (chip->pdata && chip->pdata->setup) {
+ ret = chip->pdata->setup(client, chip->gpio_chip->base,
+ chip->gpio_chip->ngpio,
+ chip->pdata->context);
if (ret < 0)
dev_warn(&client->dev, "setup failed, %d\n", ret);
}
@@ -343,20 +331,19 @@ static int __devinit pca953x_probe(struct i2c_client
*client,
return 0;
out_failed:
- kfree(chip->dyn_pdata);
kfree(chip);
return ret;
}
static int pca953x_remove(struct i2c_client *client)
{
- struct pca953x_platform_data *pdata = client->dev.platform_data;
struct pca953x_chip *chip = i2c_get_clientdata(client);
int ret = 0;
- if (pdata->teardown) {
- ret = pdata->teardown(client, chip->gpio_chip->base,
- chip->gpio_chip->ngpio, pdata->context);
+ if (chip->pdata && chip->pdata->teardown) {
+ ret = chip->pdata->teardown(client, chip->gpio_chip->base,
+ chip->gpio_chip->ngpio,
+ chip->pdata->context);
if (ret < 0) {
dev_err(&client->dev, "%s failed, %d\n",
"teardown", ret);
@@ -371,7 +358,6 @@ static int pca953x_remove(struct i2c_client *client)
return ret;
}
- kfree(chip->dyn_pdata);
kfree(chip);
return 0;
}
--
1.6.5
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