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@@ -41,14 +41,19 @@
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*/
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#include <linux/acpi.h>
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-#include <linux/module.h>
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-#include <linux/delay.h>
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-#include <linux/string.h>
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#include <linux/ctype.h>
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-#include <linux/leds.h>
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+#include <linux/delay.h>
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#include <linux/err.h>
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+#include <linux/gpio.h>
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#include <linux/i2c.h>
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+#include <linux/leds.h>
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+#include <linux/module.h>
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+#include <linux/of_device.h>
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+#include <linux/of.h>
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#include <linux/slab.h>
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+#include <linux/string.h>
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+
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+#include <dt-bindings/leds/leds-pca955x.h>
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/* LED select registers determine the source that drives LED outputs */
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#define PCA955X_LS_LED_ON 0x0 /* Output LOW */
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@@ -115,6 +120,9 @@ struct pca955x {
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struct pca955x_led *leds;
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struct pca955x_chipdef *chipdef;
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struct i2c_client *client;
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+#ifdef CONFIG_LEDS_PCA955X_GPIO
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+ struct gpio_chip gpio;
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+#endif
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};
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struct pca955x_led {
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@@ -122,6 +130,13 @@ struct pca955x_led {
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struct led_classdev led_cdev;
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int led_num; /* 0 .. 15 potentially */
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char name[32];
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+ u32 type;
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+ const char *default_trigger;
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+};
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+
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+struct pca955x_platform_data {
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+ struct pca955x_led *leds;
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+ int num_leds;
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};
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/* 8 bits per input register */
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@@ -150,13 +165,18 @@ static inline u8 pca955x_ledsel(u8 oldval, int led_num, int state)
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* Write to frequency prescaler register, used to program the
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* period of the PWM output. period = (PSCx + 1) / 38
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*/
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-static void pca955x_write_psc(struct i2c_client *client, int n, u8 val)
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+static int pca955x_write_psc(struct i2c_client *client, int n, u8 val)
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{
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struct pca955x *pca955x = i2c_get_clientdata(client);
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+ int ret;
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- i2c_smbus_write_byte_data(client,
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+ ret = i2c_smbus_write_byte_data(client,
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pca95xx_num_input_regs(pca955x->chipdef->bits) + 2*n,
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val);
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+ if (ret < 0)
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+ dev_err(&client->dev, "%s: reg 0x%x, val 0x%x, err %d\n",
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+ __func__, n, val, ret);
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+ return ret;
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}
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/*
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@@ -166,38 +186,56 @@ static void pca955x_write_psc(struct i2c_client *client, int n, u8 val)
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*
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* Duty cycle is (256 - PWMx) / 256
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*/
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-static void pca955x_write_pwm(struct i2c_client *client, int n, u8 val)
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+static int pca955x_write_pwm(struct i2c_client *client, int n, u8 val)
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{
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struct pca955x *pca955x = i2c_get_clientdata(client);
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+ int ret;
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- i2c_smbus_write_byte_data(client,
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+ ret = i2c_smbus_write_byte_data(client,
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pca95xx_num_input_regs(pca955x->chipdef->bits) + 1 + 2*n,
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val);
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+ if (ret < 0)
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+ dev_err(&client->dev, "%s: reg 0x%x, val 0x%x, err %d\n",
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+ __func__, n, val, ret);
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+ return ret;
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}
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/*
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* Write to LED selector register, which determines the source that
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* drives the LED output.
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*/
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-static void pca955x_write_ls(struct i2c_client *client, int n, u8 val)
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+static int pca955x_write_ls(struct i2c_client *client, int n, u8 val)
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{
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struct pca955x *pca955x = i2c_get_clientdata(client);
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+ int ret;
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- i2c_smbus_write_byte_data(client,
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+ ret = i2c_smbus_write_byte_data(client,
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pca95xx_num_input_regs(pca955x->chipdef->bits) + 4 + n,
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val);
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+ if (ret < 0)
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+ dev_err(&client->dev, "%s: reg 0x%x, val 0x%x, err %d\n",
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+ __func__, n, val, ret);
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+ return ret;
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}
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/*
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* Read the LED selector register, which determines the source that
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* drives the LED output.
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*/
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-static u8 pca955x_read_ls(struct i2c_client *client, int n)
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+static int pca955x_read_ls(struct i2c_client *client, int n, u8 *val)
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{
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struct pca955x *pca955x = i2c_get_clientdata(client);
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+ int ret;
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- return (u8) i2c_smbus_read_byte_data(client,
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+ ret = i2c_smbus_read_byte_data(client,
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pca95xx_num_input_regs(pca955x->chipdef->bits) + 4 + n);
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+ if (ret < 0) {
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+ dev_err(&client->dev, "%s: reg 0x%x, err %d\n",
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+ __func__, n, ret);
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+ return ret;
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+ }
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+ *val = (u8)ret;
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+ return 0;
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}
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static int pca955x_led_set(struct led_classdev *led_cdev,
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@@ -208,6 +246,7 @@ static int pca955x_led_set(struct led_classdev *led_cdev,
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u8 ls;
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int chip_ls; /* which LSx to use (0-3 potentially) */
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int ls_led; /* which set of bits within LSx to use (0-3) */
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+ int ret;
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pca955x_led = container_of(led_cdev, struct pca955x_led, led_cdev);
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pca955x = pca955x_led->pca955x;
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@@ -217,7 +256,9 @@ static int pca955x_led_set(struct led_classdev *led_cdev,
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mutex_lock(&pca955x->lock);
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- ls = pca955x_read_ls(pca955x->client, chip_ls);
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+ ret = pca955x_read_ls(pca955x->client, chip_ls, &ls);
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+ if (ret)
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+ goto out;
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switch (value) {
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case LED_FULL:
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@@ -237,18 +278,159 @@ static int pca955x_led_set(struct led_classdev *led_cdev,
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* OFF, HALF, or FULL. But, this is probably better than
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* just turning off for all other values.
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*/
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- pca955x_write_pwm(pca955x->client, 1,
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- 255 - value);
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+ ret = pca955x_write_pwm(pca955x->client, 1, 255 - value);
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+ if (ret)
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+ goto out;
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ls = pca955x_ledsel(ls, ls_led, PCA955X_LS_BLINK1);
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break;
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}
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- pca955x_write_ls(pca955x->client, chip_ls, ls);
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+ ret = pca955x_write_ls(pca955x->client, chip_ls, ls);
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+out:
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mutex_unlock(&pca955x->lock);
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+ return ret;
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+}
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+
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+#ifdef CONFIG_LEDS_PCA955X_GPIO
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+/*
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+ * Read the INPUT register, which contains the state of LEDs.
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+ */
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+static int pca955x_read_input(struct i2c_client *client, int n, u8 *val)
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+{
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+ int ret = i2c_smbus_read_byte_data(client, n);
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+
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+ if (ret < 0) {
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+ dev_err(&client->dev, "%s: reg 0x%x, err %d\n",
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+ __func__, n, ret);
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+ return ret;
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+ }
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+ *val = (u8)ret;
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return 0;
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+
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+}
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+
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+static int pca955x_gpio_request_pin(struct gpio_chip *gc, unsigned int offset)
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+{
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+ struct pca955x *pca955x = gpiochip_get_data(gc);
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+ struct pca955x_led *led = &pca955x->leds[offset];
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+
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+ if (led->type == PCA955X_TYPE_GPIO)
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+ return 0;
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+
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+ return -EBUSY;
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+}
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+
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+static int pca955x_set_value(struct gpio_chip *gc, unsigned int offset,
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+ int val)
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+{
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+ struct pca955x *pca955x = gpiochip_get_data(gc);
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+ struct pca955x_led *led = &pca955x->leds[offset];
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+
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+ if (val)
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+ return pca955x_led_set(&led->led_cdev, LED_FULL);
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+ else
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+ return pca955x_led_set(&led->led_cdev, LED_OFF);
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+}
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+
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+static void pca955x_gpio_set_value(struct gpio_chip *gc, unsigned int offset,
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+ int val)
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+{
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+ pca955x_set_value(gc, offset, val);
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+}
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+
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+static int pca955x_gpio_get_value(struct gpio_chip *gc, unsigned int offset)
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+{
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+ struct pca955x *pca955x = gpiochip_get_data(gc);
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+ struct pca955x_led *led = &pca955x->leds[offset];
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+ u8 reg = 0;
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+
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+ /* There is nothing we can do about errors */
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+ pca955x_read_input(pca955x->client, led->led_num / 8, ®);
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+
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+ return !!(reg & (1 << (led->led_num % 8)));
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+}
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+
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+static int pca955x_gpio_direction_input(struct gpio_chip *gc,
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+ unsigned int offset)
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+{
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+ /* To use as input ensure pin is not driven */
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+ return pca955x_set_value(gc, offset, 0);
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+}
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+
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+static int pca955x_gpio_direction_output(struct gpio_chip *gc,
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+ unsigned int offset, int val)
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+{
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+ return pca955x_set_value(gc, offset, val);
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}
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+#endif /* CONFIG_LEDS_PCA955X_GPIO */
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+
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+#if IS_ENABLED(CONFIG_OF)
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+static struct pca955x_platform_data *
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+pca955x_pdata_of_init(struct i2c_client *client, struct pca955x_chipdef *chip)
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+{
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+ struct device_node *np = client->dev.of_node;
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+ struct device_node *child;
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+ struct pca955x_platform_data *pdata;
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+ int count;
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+
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+ count = of_get_child_count(np);
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+ if (!count || count > chip->bits)
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+ return ERR_PTR(-ENODEV);
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+
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+ pdata = devm_kzalloc(&client->dev, sizeof(*pdata), GFP_KERNEL);
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+ if (!pdata)
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+ return ERR_PTR(-ENOMEM);
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+
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+ pdata->leds = devm_kzalloc(&client->dev,
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+ sizeof(struct pca955x_led) * chip->bits,
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+ GFP_KERNEL);
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+ if (!pdata->leds)
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+ return ERR_PTR(-ENOMEM);
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+
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+ for_each_child_of_node(np, child) {
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+ const char *name;
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+ u32 reg;
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+ int res;
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+
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+ res = of_property_read_u32(child, "reg", ®);
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+ if ((res != 0) || (reg >= chip->bits))
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+ continue;
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+
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+ if (of_property_read_string(child, "label", &name))
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+ name = child->name;
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+
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+ snprintf(pdata->leds[reg].name, sizeof(pdata->leds[reg].name),
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+ "%s", name);
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+
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+ pdata->leds[reg].type = PCA955X_TYPE_LED;
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+ of_property_read_u32(child, "type", &pdata->leds[reg].type);
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+ of_property_read_string(child, "linux,default-trigger",
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+ &pdata->leds[reg].default_trigger);
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+ }
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+
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+ pdata->num_leds = chip->bits;
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+
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+ return pdata;
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+}
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+
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+static const struct of_device_id of_pca955x_match[] = {
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+ { .compatible = "nxp,pca9550", .data = (void *)pca9550 },
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+ { .compatible = "nxp,pca9551", .data = (void *)pca9551 },
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+ { .compatible = "nxp,pca9552", .data = (void *)pca9552 },
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+ { .compatible = "nxp,pca9553", .data = (void *)pca9553 },
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+ {},
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+};
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+
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+MODULE_DEVICE_TABLE(of, of_pca955x_match);
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+#else
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+static struct pca955x_platform_data *
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+pca955x_pdata_of_init(struct i2c_client *client, struct pca955x_chipdef *chip)
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+{
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+ return ERR_PTR(-ENODEV);
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+}
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+#endif
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static int pca955x_probe(struct i2c_client *client,
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const struct i2c_device_id *id)
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@@ -257,8 +439,9 @@ static int pca955x_probe(struct i2c_client *client,
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struct pca955x_led *pca955x_led;
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struct pca955x_chipdef *chip;
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struct i2c_adapter *adapter;
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- struct led_platform_data *pdata;
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int i, err;
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+ struct pca955x_platform_data *pdata;
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+ int ngpios = 0;
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if (id) {
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chip = &pca955x_chipdefs[id->driver_data];
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@@ -272,6 +455,11 @@ static int pca955x_probe(struct i2c_client *client,
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}
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adapter = to_i2c_adapter(client->dev.parent);
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pdata = dev_get_platdata(&client->dev);
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+ if (!pdata) {
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+ pdata = pca955x_pdata_of_init(client, chip);
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+ if (IS_ERR(pdata))
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+ return PTR_ERR(pdata);
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+ }
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/* Make sure the slave address / chip type combo given is possible */
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if ((client->addr & ~((1 << chip->slv_addr_shift) - 1)) !=
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@@ -288,13 +476,11 @@ static int pca955x_probe(struct i2c_client *client,
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if (!i2c_check_functionality(adapter, I2C_FUNC_SMBUS_BYTE_DATA))
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return -EIO;
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- if (pdata) {
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- if (pdata->num_leds != chip->bits) {
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- dev_err(&client->dev, "board info claims %d LEDs"
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- " on a %d-bit chip\n",
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- pdata->num_leds, chip->bits);
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- return -ENODEV;
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- }
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+ if (pdata->num_leds != chip->bits) {
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+ dev_err(&client->dev,
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+ "board info claims %d LEDs on a %d-bit chip\n",
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+ pdata->num_leds, chip->bits);
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+ return -ENODEV;
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}
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pca955x = devm_kzalloc(&client->dev, sizeof(*pca955x), GFP_KERNEL);
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@@ -316,60 +502,92 @@ static int pca955x_probe(struct i2c_client *client,
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pca955x_led = &pca955x->leds[i];
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pca955x_led->led_num = i;
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pca955x_led->pca955x = pca955x;
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+ pca955x_led->type = pdata->leds[i].type;
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+
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+ switch (pca955x_led->type) {
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+ case PCA955X_TYPE_NONE:
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+ break;
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+ case PCA955X_TYPE_GPIO:
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+ ngpios++;
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+ break;
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+ case PCA955X_TYPE_LED:
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+ /*
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+ * Platform data can specify LED names and
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+ * default triggers
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+ */
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+ if (pdata->leds[i].name[0] == '\0')
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+ snprintf(pdata->leds[i].name,
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+ sizeof(pdata->leds[i].name), "%d", i);
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+
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+ snprintf(pca955x_led->name,
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+ sizeof(pca955x_led->name), "pca955x:%s",
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+ pdata->leds[i].name);
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- /* Platform data can specify LED names and default triggers */
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- if (pdata) {
|
|
|
- if (pdata->leds[i].name)
|
|
|
- snprintf(pca955x_led->name,
|
|
|
- sizeof(pca955x_led->name), "pca955x:%s",
|
|
|
- pdata->leds[i].name);
|
|
|
if (pdata->leds[i].default_trigger)
|
|
|
pca955x_led->led_cdev.default_trigger =
|
|
|
pdata->leds[i].default_trigger;
|
|
|
- } else {
|
|
|
- snprintf(pca955x_led->name, sizeof(pca955x_led->name),
|
|
|
- "pca955x:%d", i);
|
|
|
- }
|
|
|
|
|
|
- pca955x_led->led_cdev.name = pca955x_led->name;
|
|
|
- pca955x_led->led_cdev.brightness_set_blocking = pca955x_led_set;
|
|
|
+ pca955x_led->led_cdev.name = pca955x_led->name;
|
|
|
+ pca955x_led->led_cdev.brightness_set_blocking =
|
|
|
+ pca955x_led_set;
|
|
|
|
|
|
- err = led_classdev_register(&client->dev,
|
|
|
- &pca955x_led->led_cdev);
|
|
|
- if (err < 0)
|
|
|
- goto exit;
|
|
|
- }
|
|
|
+ err = devm_led_classdev_register(&client->dev,
|
|
|
+ &pca955x_led->led_cdev);
|
|
|
+ if (err)
|
|
|
+ return err;
|
|
|
|
|
|
- /* Turn off LEDs */
|
|
|
- for (i = 0; i < pca95xx_num_led_regs(chip->bits); i++)
|
|
|
- pca955x_write_ls(client, i, 0x55);
|
|
|
+ /* Turn off LED */
|
|
|
+ err = pca955x_led_set(&pca955x_led->led_cdev, LED_OFF);
|
|
|
+ if (err)
|
|
|
+ return err;
|
|
|
+ }
|
|
|
+ }
|
|
|
|
|
|
/* PWM0 is used for half brightness or 50% duty cycle */
|
|
|
- pca955x_write_pwm(client, 0, 255-LED_HALF);
|
|
|
+ err = pca955x_write_pwm(client, 0, 255 - LED_HALF);
|
|
|
+ if (err)
|
|
|
+ return err;
|
|
|
|
|
|
/* PWM1 is used for variable brightness, default to OFF */
|
|
|
- pca955x_write_pwm(client, 1, 0);
|
|
|
+ err = pca955x_write_pwm(client, 1, 0);
|
|
|
+ if (err)
|
|
|
+ return err;
|
|
|
|
|
|
/* Set to fast frequency so we do not see flashing */
|
|
|
- pca955x_write_psc(client, 0, 0);
|
|
|
- pca955x_write_psc(client, 1, 0);
|
|
|
-
|
|
|
- return 0;
|
|
|
-
|
|
|
-exit:
|
|
|
- while (i--)
|
|
|
- led_classdev_unregister(&pca955x->leds[i].led_cdev);
|
|
|
-
|
|
|
- return err;
|
|
|
-}
|
|
|
-
|
|
|
-static int pca955x_remove(struct i2c_client *client)
|
|
|
-{
|
|
|
- struct pca955x *pca955x = i2c_get_clientdata(client);
|
|
|
- int i;
|
|
|
-
|
|
|
- for (i = 0; i < pca955x->chipdef->bits; i++)
|
|
|
- led_classdev_unregister(&pca955x->leds[i].led_cdev);
|
|
|
+ err = pca955x_write_psc(client, 0, 0);
|
|
|
+ if (err)
|
|
|
+ return err;
|
|
|
+ err = pca955x_write_psc(client, 1, 0);
|
|
|
+ if (err)
|
|
|
+ return err;
|
|
|
+
|
|
|
+#ifdef CONFIG_LEDS_PCA955X_GPIO
|
|
|
+ if (ngpios) {
|
|
|
+ pca955x->gpio.label = "gpio-pca955x";
|
|
|
+ pca955x->gpio.direction_input = pca955x_gpio_direction_input;
|
|
|
+ pca955x->gpio.direction_output = pca955x_gpio_direction_output;
|
|
|
+ pca955x->gpio.set = pca955x_gpio_set_value;
|
|
|
+ pca955x->gpio.get = pca955x_gpio_get_value;
|
|
|
+ pca955x->gpio.request = pca955x_gpio_request_pin;
|
|
|
+ pca955x->gpio.can_sleep = 1;
|
|
|
+ pca955x->gpio.base = -1;
|
|
|
+ pca955x->gpio.ngpio = ngpios;
|
|
|
+ pca955x->gpio.parent = &client->dev;
|
|
|
+ pca955x->gpio.owner = THIS_MODULE;
|
|
|
+
|
|
|
+ err = devm_gpiochip_add_data(&client->dev, &pca955x->gpio,
|
|
|
+ pca955x);
|
|
|
+ if (err) {
|
|
|
+ /* Use data->gpio.dev as a flag for freeing gpiochip */
|
|
|
+ pca955x->gpio.parent = NULL;
|
|
|
+ dev_warn(&client->dev, "could not add gpiochip\n");
|
|
|
+ return err;
|
|
|
+ }
|
|
|
+ dev_info(&client->dev, "gpios %i...%i\n",
|
|
|
+ pca955x->gpio.base, pca955x->gpio.base +
|
|
|
+ pca955x->gpio.ngpio - 1);
|
|
|
+ }
|
|
|
+#endif
|
|
|
|
|
|
return 0;
|
|
|
}
|
|
|
@@ -378,9 +596,9 @@ static struct i2c_driver pca955x_driver = {
|
|
|
.driver = {
|
|
|
.name = "leds-pca955x",
|
|
|
.acpi_match_table = ACPI_PTR(pca955x_acpi_ids),
|
|
|
+ .of_match_table = of_match_ptr(of_pca955x_match),
|
|
|
},
|
|
|
.probe = pca955x_probe,
|
|
|
- .remove = pca955x_remove,
|
|
|
.id_table = pca955x_id,
|
|
|
};
|
|
|
|
Linus Torvalds