Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932360Ab3JNWiS (ORCPT ); Mon, 14 Oct 2013 18:38:18 -0400 Received: from ns.pmeerw.net ([87.118.82.44]:34460 "EHLO pmeerw.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932218Ab3JNWiP (ORCPT ); Mon, 14 Oct 2013 18:38:15 -0400 Date: Tue, 15 Oct 2013 00:38:13 +0200 (CEST) From: Peter Meerwald To: =?UTF-8?Q?Maximilian_G=C3=BCntner?= cc: Bryan Wu , Richard Purdie , linux-kernel , linux-leds Subject: Re: [PATCH] leds: Added driver for the NXP PCA9685 I2C chip In-Reply-To: <2819232.mPNW6mO2uH@titan> Message-ID: References: <2819232.mPNW6mO2uH@titan> User-Agent: Alpine 2.01 (DEB 1266 2009-07-14) MIME-Version: 1.0 Content-Type: MULTIPART/MIXED; BOUNDARY="1985424466-1406653067-1381790293=:26447" Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 10214 Lines: 346 This message is in MIME format. The first part should be readable text, while the remaining parts are likely unreadable without MIME-aware tools. --1985424466-1406653067-1381790293=:26447 Content-Type: TEXT/PLAIN; charset=UTF-8 Content-Transfer-Encoding: 8BIT > The NXP PCA9685 supports 16 channels/leds using a 12-bit PWM (4095 > levels of brightness) > This driver supports configuration using platform_data. some nitpicking inline > Signed-off-by: Maximilian Güntner > --- > drivers/leds/Kconfig | 10 ++ > drivers/leds/Makefile | 1 + > drivers/leds/leds-pca9685.c | 219 +++++++++++++++++++++++++++++ > include/linux/platform_data/leds-pca9685.h | 34 +++++ > 4 files changed, 264 insertions(+) > create mode 100644 drivers/leds/leds-pca9685.c > create mode 100644 include/linux/platform_data/leds-pca9685.h > > diff --git a/drivers/leds/Kconfig b/drivers/leds/Kconfig > index 875bbe4..98268b3 100644 > --- a/drivers/leds/Kconfig > +++ b/drivers/leds/Kconfig > @@ -300,6 +300,16 @@ config LEDS_PCA963X > LED driver chip accessed via the I2C bus. Supported > devices include PCA9633 and PCA9634 > > +config LEDS_PCA9685 > + tristate "LED support for PCA9685 I2C chip" > + depends on LEDS_CLASS > + depends on I2C > + help > + This option enables support for LEDs connected to the PCA9685 > + LED driver chips accessed via the I2C bus. chip > + The PCA9685 offers 12-bit PWM (4095 levels of brightness) on > + 16 individual channels. > + > config LEDS_WM831X_STATUS > tristate "LED support for status LEDs on WM831x PMICs" > depends on LEDS_CLASS > diff --git a/drivers/leds/Makefile b/drivers/leds/Makefile > index 8979b0b..3cd76db 100644 > --- a/drivers/leds/Makefile > +++ b/drivers/leds/Makefile > @@ -36,6 +36,7 @@ obj-$(CONFIG_LEDS_OT200) += leds-ot200.o > obj-$(CONFIG_LEDS_FSG) += leds-fsg.o > obj-$(CONFIG_LEDS_PCA955X) += leds-pca955x.o > obj-$(CONFIG_LEDS_PCA963X) += leds-pca963x.o > +obj-$(CONFIG_LEDS_PCA9685) += leds-pca9685.o > obj-$(CONFIG_LEDS_DA903X) += leds-da903x.o > obj-$(CONFIG_LEDS_DA9052) += leds-da9052.o > obj-$(CONFIG_LEDS_WM831X_STATUS) += leds-wm831x-status.o > diff --git a/drivers/leds/leds-pca9685.c b/drivers/leds/leds-pca9685.c > new file mode 100644 > index 0000000..a2078bf > --- /dev/null > +++ b/drivers/leds/leds-pca9685.c > @@ -0,0 +1,219 @@ > +/* > + * Copyright 2013 Maximilian Güntner > + * > + * This file is subject to the terms and conditions of version 2 of > + * the GNU General Public License. See the file COPYING in the main > + * directory of this archive for more details. > + * > + * Based on leds-pca963x.c driver by > + * Peter Meerwald > + * > + * Driver for the NXP PCA9685 12-Bit I2C chip. this could be more descriptive: 12-bit PWM LED driver chip > + * > + */ > + > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > + > +#include > + > +/* Register Addresses */ > +#define PCA9685_MODE1 0x00 > +#define PCA9685_MODE2 0x01 > +#define PCA9685_LED0_ON_L 0x06 > +#define PCA9685_ALL_LED_ON_L 0xFA > + > +/* MODE1 Register */ > +#define PCA9685_ALLCALL 0x00 > +#define PCA9685_SLEEP 0x04 > +#define PCA9685_AI 0x05 > + > +/* MODE2 Register */ > +#define PCA9685_INVRT 0x04 > +#define PCA9685_OUTDRV 0x02 > + > +static const struct i2c_device_id pca9685_id[] = { > + { "pca9685", 0 }, > + { } > +}; > +MODULE_DEVICE_TABLE(i2c, pca9685_id); > + > +struct pca9685_led { > + struct i2c_client *client; > + struct work_struct work; > + u16 brightness; > + struct led_classdev led_cdev; > + int led_num; /* 0-15 */ > + char name[32]; > +}; > + > +static void pca9685_write_msg(struct i2c_client *client, u8 *buf, u8 len) > +{ > + struct i2c_msg msg = { > + .addr = client->addr, > + .flags = 0x00, > + .len = len, > + .buf = buf > + }; > + i2c_transfer(client->adapter, &msg, 1); > +} > + > +static void pca9685_all_off(struct i2c_client *client) > +{ > + u8 i2c_buffer[5] = {PCA9685_ALL_LED_ON_L, 0x00, 0x00, 0x00, 0x10}; > + pca9685_write_msg(client, i2c_buffer, 5); > +} > + > +static void pca9685_led_work(struct work_struct *work) > +{ > + struct pca9685_led *pca9685; > + u16 brightness; > + u8 i2c_buffer[5]; > + pca9685 = container_of(work, struct pca9685_led, work); > + /* > + * 4095 is the maximum brightness, so we set the ON time to 0x1000 > + * which disables the PWM generator for that LED > + */ > + if (pca9685->brightness == 4095) > + brightness = 4096; why not check for 4095 instead of 4096 below and save this if statement? > + else > + brightness = pca9685->brightness; > + > + i2c_buffer[0] = PCA9685_LED0_ON_L + 4 * pca9685->led_num; > + > + if (brightness == 4096) > + *((u16 *)(i2c_buffer+1)) = cpu_to_le16(0x1000); > + else > + *((u16 *)(i2c_buffer+1)) = 0x0000; > + if (brightness == 0) > + *((u16 *)(i2c_buffer+3)) = cpu_to_le16(0x1000); > + else if (brightness == 4096) > + *((u16 *)(i2c_buffer+3)) = 0x0000; > + else > + *((u16 *)(i2c_buffer+3)) = cpu_to_le16(brightness); > + > + pca9685_write_msg(pca9685->client, i2c_buffer, 5); > +} > + > +static void pca9685_led_set(struct led_classdev *led_cdev, > + enum led_brightness value) > +{ > + struct pca9685_led *pca9685; > + pca9685 = container_of(led_cdev, struct pca9685_led, led_cdev); > + pca9685->brightness = value; > + > + schedule_work(&pca9685->work); > +} > + > +static int pca9685_probe(struct i2c_client *client, > + const struct i2c_device_id *id) > +{ > + struct pca9685_led *pca9685; > + struct pca9685_platform_data *pdata; > + int err; > + u8 i; > + > + pdata = dev_get_platdata(&client->dev); > + > + if (pdata) { > + if (pdata->leds.num_leds < 1 || pdata->leds.num_leds > 15) { > + dev_err(&client->dev, "board info must claim 1-16 LEDs"); > + return -EINVAL; > + } > + } > + > + pca9685 = devm_kzalloc(&client->dev, 16 * sizeof(*pca9685), GFP_KERNEL); > + > + if (!pca9685) > + return -ENOMEM; > + > + i2c_set_clientdata(client, pca9685); > + pca9685_all_off(client); > + > + for (i = 0; i < 16; i++) { > + pca9685[i].client = client; > + pca9685[i].led_num = i; > + pca9685[i].name[0] = '\0'; > + if (pdata && i < pdata->leds.num_leds) { > + if (pdata->leds.leds[i].name) > + strncpy(pca9685[i].name, > + pdata->leds.leds[i].name, > + sizeof(pca9685[i].name)-1); > + if (pdata->leds.leds[i].default_trigger) > + pca9685[i].led_cdev.default_trigger = > + pdata->leds.leds[i].default_trigger; > + } > + if (strlen(pca9685[i].name) == 0) { > + /* > + * Write adapter and address to the name as well. > + * Otherwise multiple chips attached to one host would > + * not work. > + */ > + snprintf(pca9685[i].name, sizeof(pca9685[i].name), > + "pca9685:%d:x%.2x:%d", > + client->adapter->nr, client->addr, i); > + } > + pca9685[i].led_cdev.name = pca9685[i].name; > + pca9685[i].led_cdev.max_brightness = 0xfff; > + pca9685[i].led_cdev.brightness_set = pca9685_led_set; > + > + INIT_WORK(&pca9685[i].work, pca9685_led_work); > + err = led_classdev_register(&client->dev, &pca9685[i].led_cdev); > + if (err < 0) > + goto exit; > + } > + if (pdata) > + i2c_smbus_write_byte_data(client, PCA9685_MODE2, > + pdata->outdrv << PCA9685_OUTDRV | > + pdata->inverted << PCA9685_INVRT); > + else > + i2c_smbus_write_byte_data(client, PCA9685_MODE2, > + PCA9685_TOTEM_POLE << PCA9685_OUTDRV); > + /* Enable Auto-Increment, enable oscillator, ALLCALL/SUBADDR disabled */ > + i2c_smbus_write_byte_data(client, PCA9685_MODE1, 1 << PCA9685_AI); maybe BIT(PCA9685_AI) > + > + return 0; > + > +exit: > + while (i--) { > + led_classdev_unregister(&pca9685[i].led_cdev); > + cancel_work_sync(&pca9685[i].work); > + } > + return err; > +} > + > +static int pca9685_remove(struct i2c_client *client) > +{ > + struct pca9685_led *pca9685 = i2c_get_clientdata(client); > + u8 i; > + > + for (i = 0; i < 16; i++) { > + led_classdev_unregister(&pca9685[i].led_cdev); > + cancel_work_sync(&pca9685[i].work); > + } > + pca9685_all_off(client); > + return 0; > +} > + > +static struct i2c_driver pca9685_driver = { > + .driver = { > + .name = "leds-pca9685", > + .owner = THIS_MODULE, > + }, > + .probe = pca9685_probe, > + .remove = pca9685_remove, > + .id_table = pca9685_id, > +}; > + > +module_i2c_driver(pca9685_driver); > + > +MODULE_AUTHOR("Maximilian Güntner "); > +MODULE_DESCRIPTION("PCA9685 LED Driver"); > +MODULE_LICENSE("GPL v2"); > diff --git a/include/linux/platform_data/leds-pca9685.h b/include/linux/platform_data/leds-pca9685.h > new file mode 100644 > index 0000000..cce28b8 > --- /dev/null > +++ b/include/linux/platform_data/leds-pca9685.h > @@ -0,0 +1,34 @@ > +/* > + * Copyright 2013 Maximilian Güntner > + * > + * This file is subject to the terms and conditions of version 2 of > + * the GNU General Public License. See the file COPYING in the main > + * directory of this archive for more details. > + * > + * Based on leds-pca963x.h by Peter Meerwald > + * > + * LED driver for the NXP PCA9685 PWM chip > + * > + */ > + > +#ifndef __LINUX_PCA9685_H > +#define __LINUX_PCA9685_H > +#include > + > +enum pca9685_outdrv { > + PCA9685_OPEN_DRAIN, > + PCA9685_TOTEM_POLE, > +}; > + > +enum pca9685_inverted { > + PCA9685_NOT_INVERTED, > + PCA9685_INVERTED, > +}; > + > +struct pca9685_platform_data { > + struct led_platform_data leds; > + enum pca9685_outdrv outdrv; > + enum pca9685_inverted inverted; > +}; > + > +#endif /* __LINUX_PCA9685_H */ > -- Peter Meerwald +43-664-2444418 (mobile) --1985424466-1406653067-1381790293=:26447-- -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/