[PATCH 1/2] max7315: Add LED support to the driver
From: Alan Cox
Date: Fri Oct 01 2010 - 12:04:15 EST
From: jianwei.yang <jianwei.yang@xxxxxxxxx>
The max7315 also has LED interfaces. Export them as LED class objects when
we find the device. We don't require the LEDS class is enabled to use this
driver as it seems preferable not for drag in the layer for those who don't
need it.
Signed-off-by: jianwei.yang <jianwei.yang@xxxxxxxxx>
[bug fixes]
Signed-off-by: Jacob Pan <jacob.jun.pan@xxxxxxxxxxxxxxx>
[Some minor tidying]
Signed-off-by: Alan Cox <alan@xxxxxxxxxxxxxxx>
---
drivers/gpio/max7315.h | 82 +++++++++++++++++++
drivers/gpio/pca953x.c | 203 ++++++++++++++++++++++++++++++++++++++++++++++++
2 files changed, 283 insertions(+), 2 deletions(-)
create mode 100644 drivers/gpio/max7315.h
diff --git a/drivers/gpio/max7315.h b/drivers/gpio/max7315.h
new file mode 100644
index 0000000..a917002
--- /dev/null
+++ b/drivers/gpio/max7315.h
@@ -0,0 +1,82 @@
+/*
+ * max7315.h - GPIO expander MAX7315 driver header
+ *
+ * Copyright (C) 2010 Aava Mobile Oy
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <linux/leds.h>
+#include <linux/workqueue.h>
+
+#define MAX7315_INPUT 0x00
+#define MAX7315_BLINK0 0x01
+#define MAX7315_DIRECTION 0x03
+#define MAX7315_BLINK1 0x09
+#define MAX7315_MG8 0x0E
+#define MAX7315_CONF 0x0F
+#define MAX7315_INTNS0 0x10
+#define MAX7315_INTNS1 0x11
+#define MAX7315_INTNS2 0x12
+#define MAX7315_INTNS3 0x13
+/* configuration register masks */
+#define MAX7315_CONF_BEN 0x01
+#define MAX7315_CONF_BFLIP 0x02
+#define MAX7315_CONF_GLINTNS 0x04
+#define MAX7315_CONF_INTEN 0x08
+#define MAX7315_CONF_INTOC1 0x10
+#define MAX7315_CONF_INTOC2 0x20
+#define MAX7315_CONF_RSRVD 0x40
+#define MAX7315_CONF_INTSTS 0x80
+/* led pin register mask */
+#define MAX7315_P2_MASK 0x04
+/* PWM enable mask */
+#define MAX7315_PWM_MASK 0xFF
+/* BLINK mask */
+#define MAX7315_BLINKMASK_P2 (1 << 2)
+/* period in ms */
+#define MAX7315_PERIOD_MIN 0
+#define MAX7315_PERIOD_MAX 1600
+/* duty cycle range: 0, 1/16, 2/16, ... 15/16 */
+#define MAX7315_DCYCLE_MIN 0
+#define MAX7315_DCYCLE_MAX 100
+#define MAX7315_BLINK_PRESET0 75
+#define MAX7315_BLINK_PRESET1 60
+#define MAX7315_BLINK_PRESET2 15
+#define MAX7315_BLINK_DELAY0 100
+#define MAX7315_BLINK_DELAY1 250
+#define MAX7315_BLINK_DELAY2 500
+#define MAX7315_DUTY_MAX 0xF
+
+/* XXX STATUS_MAX needs to be updated in case more modes are added XXX */
+
+#define MAX7315_LED_STATUS_MAX 3
+#define MAX7315_LEDS_MAX 8
+
+enum max7315_status {
+ MAX7315_LED_STATUS_OFF,
+ MAX7315_LED_STATUS_ON,
+ MAX7315_LED_STATUS_BLINK0,
+ MAX7315_LED_STATUS_BLINK1,
+};
+
+struct max7315_led_data {
+ u8 id;
+ const char *name;
+ enum max7315_status status;
+ struct led_classdev ldev;
+ struct i2c_client *client;
+ struct work_struct work;
+};
diff --git a/drivers/gpio/pca953x.c b/drivers/gpio/pca953x.c
index a2b12aa..20bcc96 100644
--- a/drivers/gpio/pca953x.c
+++ b/drivers/gpio/pca953x.c
@@ -24,6 +24,8 @@
#include <linux/of_gpio.h>
#endif
+#include "max7315.h"
+
#define PCA953X_INPUT 0
#define PCA953X_OUTPUT 1
#define PCA953X_INVERT 2
@@ -31,6 +33,7 @@
#define PCA953X_GPIOS 0x00FF
#define PCA953X_INT 0x0100
+#define PCA953X_LED 0x0200
static const struct i2c_device_id pca953x_id[] = {
{ "pca9534", 8 | PCA953X_INT, },
@@ -47,7 +50,7 @@ static const struct i2c_device_id pca953x_id[] = {
{ "max7310", 8, },
{ "max7312", 16 | PCA953X_INT, },
{ "max7313", 16 | PCA953X_INT, },
- { "max7315", 8 | PCA953X_INT, },
+ { "max7315", 8 | PCA953X_INT | PCA953X_LED, },
{ "pca6107", 8 | PCA953X_INT, },
{ "tca6408", 8 | PCA953X_INT, },
{ "tca6416", 16 | PCA953X_INT, },
@@ -74,6 +77,12 @@ struct pca953x_chip {
struct pca953x_platform_data *dyn_pdata;
struct gpio_chip gpio_chip;
const char *const *names;
+
+#ifdef CONFIG_LEDS_CLASS
+ struct max7315_led_data leds[MAX7315_LEDS_MAX];
+ struct work_struct work;
+ uint8_t leds_size;
+#endif
};
static int pca953x_write_reg(struct pca953x_chip *chip, int reg, uint16_t val)
@@ -483,6 +492,190 @@ pca953x_get_alt_pdata(struct i2c_client *client)
}
#endif
+
+#ifdef CONFIG_LEDS_CLASS
+
+/**
+ * Set the led status
+ *
+ * @chip: a pca953x_chip structure
+ * @status: one of MAX7315_LED_STATUS_OFF
+ * MAX7315_LED_STATUS_ON
+ * MAX7315_LED_STATUS_BLINK0
+ * MAX7315_LED_STATUS_BLINK1
+ */
+static int max7315_led_set(struct max7315_led_data *led, u8 status)
+{
+ return 0;
+}
+
+static void max7315_led_set_brightness(struct led_classdev *led_cdev,
+ enum led_brightness brightness)
+{
+ struct max7315_led_data *led =
+ container_of(led_cdev, struct max7315_led_data, ldev);
+
+ dev_dbg(&led->client->dev, "%s: %s, %d\n",
+ __func__, led_cdev->name, brightness);
+
+ led->status = brightness;
+ schedule_work(&led->work);
+}
+
+static enum led_brightness
+ max7315_led_get_brightness(struct led_classdev *led_cdev)
+{
+ struct max7315_led_data *led =
+ container_of(led_cdev, struct max7315_led_data, ldev);
+
+ return led->status;
+}
+
+static int max7315_led_set_blink(struct led_classdev *led_cdev,
+ unsigned long *delay_on,
+ unsigned long *delay_off)
+{
+ return 0;
+}
+
+static void max7315_led_work(struct work_struct *work)
+{
+ struct max7315_led_data *led;
+
+ led = container_of(work, struct max7315_led_data, work);
+ max7315_led_set(led, led->status);
+}
+
+static int max7315_teardown_leds(struct i2c_client *client,
+ unsigned gpio, unsigned ngpio, void *context)
+{
+ int i = 0;
+ struct pca953x_chip *chip = i2c_get_clientdata(client);
+ for (i = 0; i < chip->leds_size; i++) {
+ led_classdev_unregister(&chip->leds[i].ldev);
+ cancel_work_sync(&chip->leds[i].work);
+ }
+ return 0;
+}
+
+/* Initial settings for max7315 leds */
+static int max7315_setup_leds(struct i2c_client *client,
+ unsigned gpio, unsigned ngpio, void *context)
+{
+ int i = 0, err = 0;
+ u8 conf_reg = 0;
+ uint16_t port_reg = 0;
+ struct pca953x_chip *chip = i2c_get_clientdata(client);
+
+ if (!chip) {
+ dev_err(&client->dev, "%s no client chip data\n", __func__);
+ goto exit;
+ }
+ /* Set master intensity (between 0x10-0xFF) */
+ err = pca953x_write_reg(chip, MAX7315_MG8, MAX7315_PWM_MASK);
+ if (err < 0) {
+ dev_err(&client->dev, "%s couldn't enable PWM\n", __func__);
+ goto exit;
+ }
+ /* Set BLINK1 output */
+ err = pca953x_read_reg(chip, MAX7315_BLINK1, &port_reg);
+ if (err) {
+ dev_err(&client->dev, "%s couldn't read BLINK1\n", __func__);
+ return err;
+ }
+ port_reg |= MAX7315_BLINKMASK_P2;
+ err = pca953x_write_reg(chip, MAX7315_BLINK1, port_reg);
+ if (err) {
+ dev_err(&client->dev, "%s couldn't write BLINK1\n", __func__);
+ return err;
+ }
+
+ /* Set initial configuration to leds config reg:
+ * -no blinking nor blink flip
+ * -no global intensity (each port configured separately)
+ * -interrupt enable is activated (in INT/O8)
+ * -interrupt status is logic 1 until interrupt occurs
+ * -conf: 10111000
+ * -ports 0,1,4,5,6 inputs (+3,7 not connected)
+ * -ports 2,8 outputs
+ */
+ conf_reg |= MAX7315_CONF_INTEN; /*bit 3*/
+ conf_reg |= MAX7315_CONF_INTOC1; /*bit 4*/
+ conf_reg |= MAX7315_CONF_INTOC2; /*bit 5*/
+ conf_reg |= MAX7315_CONF_INTSTS; /*bit 7*/
+ conf_reg &= ~MAX7315_CONF_BEN; /*bit 0*/
+ conf_reg &= ~MAX7315_CONF_BFLIP; /*bit 1*/
+ conf_reg &= ~MAX7315_CONF_GLINTNS; /*bit 2*/
+ conf_reg &= ~MAX7315_CONF_RSRVD; /*bit 6*/
+ err = pca953x_write_reg(chip, MAX7315_CONF, conf_reg);
+ chip->leds_size = 1;
+
+
+ for (i = 0; i < chip->leds_size; i++) {
+ struct max7315_led_data *led = &chip->leds[i];
+
+ led->client = client;
+ led->id = 2;
+ led->name = dev_name(&client->dev);
+
+ led->status = MAX7315_LED_STATUS_OFF;
+ led->ldev.name = led->name;
+ led->ldev.max_brightness = LED_FULL;
+ led->ldev.brightness_set = max7315_led_set_brightness;
+ led->ldev.blink_set = max7315_led_set_blink;
+ led->ldev.brightness_get = max7315_led_get_brightness;
+ led->ldev.flags = LED_CORE_SUSPENDRESUME;
+
+ INIT_WORK(&led->work, max7315_led_work);
+ err = led_classdev_register(&client->dev, &led->ldev);
+ if (err < 0) {
+ dev_err(&client->dev,
+ "couldn't register LED %s\n",
+ led->ldev.name);
+ goto exit;
+ }
+ /* to expose the default value to userspace */
+ led->ldev.brightness = led->status;
+
+ /* Set the default led status */
+ err = max7315_led_set(led, led->status);
+ if (err < 0) {
+ dev_err(&client->dev,
+ "%s couldn't set STATUS %d\n",
+ led->ldev.name, led->status);
+ goto exit;
+ }
+
+ }
+
+ /* Set direction and value through gpiolib */
+ if (gpio_request(chip->gpio_chip.base+2, "max7315")) {
+ pr_debug("Requesting GPIO%d failed\n",
+ chip->gpio_chip.base+2);
+ return -EIO;
+ }
+ if (gpio_direction_output(chip->gpio_chip.base+2, 0)) {
+ pr_debug("Setting GPIO%d to out failed\n",
+ chip->gpio_chip.base+2);
+ gpio_free(chip->gpio_chip.base+2);
+ return -EIO;
+ }
+ gpio_free(chip->gpio_chip.base+2);
+
+ return 0;
+
+exit:
+
+ if (i > 0)
+ for (i = i - 1; i >= 0; i--) {
+ led_classdev_unregister(&chip->leds[i].ldev);
+ cancel_work_sync(&chip->leds[i].work);
+ }
+ return err;
+}
+
+#endif
+
static int __devinit pca953x_probe(struct i2c_client *client,
const struct i2c_device_id *id)
{
@@ -542,6 +735,13 @@ static int __devinit pca953x_probe(struct i2c_client *client,
if (ret)
goto out_failed;
+#ifdef CONFIG_LEDS_CLASS
+ if (id->driver_data & PCA953X_LED) {
+ pdata->setup = max7315_setup_leds;
+ pdata->teardown = max7315_teardown_leds;
+ }
+#endif
+ i2c_set_clientdata(client, chip);
if (pdata->setup) {
ret = pdata->setup(client, chip->gpio_chip.base,
chip->gpio_chip.ngpio, pdata->context);
@@ -549,7 +749,6 @@ static int __devinit pca953x_probe(struct i2c_client *client,
dev_warn(&client->dev, "setup failed, %d\n", ret);
}
- i2c_set_clientdata(client, chip);
return 0;
out_failed:
--
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