Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1752056Ab3E0IyK (ORCPT ); Mon, 27 May 2013 04:54:10 -0400 Received: from metis.ext.pengutronix.de ([92.198.50.35]:47234 "EHLO metis.ext.pengutronix.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751370Ab3E0IyI (ORCPT ); Mon, 27 May 2013 04:54:08 -0400 From: Steffen Trumtrar To: linux-kernel@vger.kernel.org Cc: Thierry Reding , Grant Likely , Rob Herring , Rob Landley , devicetree-discuss@lists.ozlabs.org, kernel@pengutronix.de, Steffen Trumtrar Subject: [PATCH] pwm: add pca9685 driver Date: Mon, 27 May 2013 10:53:34 +0200 Message-Id: <1369644814-18369-1-git-send-email-s.trumtrar@pengutronix.de> X-Mailer: git-send-email 1.8.2.rc2 X-SA-Exim-Connect-IP: 2001:6f8:1178:2:21e:67ff:fe11:9c5c X-SA-Exim-Mail-From: str@pengutronix.de X-SA-Exim-Scanned: No (on metis.ext.pengutronix.de); SAEximRunCond expanded to false X-PTX-Original-Recipient: linux-kernel@vger.kernel.org Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 10303 Lines: 341 Add pwm driver for the NXP pca9685 16 channel pwm-led controller. The driver is really barebones at this stage. E.g. the OE' pin and therefore the according registers are not supported. The driver was tested on a HW where this pin is tied to GND. Signed-off-by: Steffen Trumtrar --- .../devicetree/bindings/pwm/nxp,pca9685-pwmled.txt | 28 +++ drivers/pwm/Kconfig | 9 + drivers/pwm/Makefile | 1 + drivers/pwm/pwm-pca9685-led.c | 245 +++++++++++++++++++++ 4 files changed, 283 insertions(+) create mode 100644 Documentation/devicetree/bindings/pwm/nxp,pca9685-pwmled.txt create mode 100644 drivers/pwm/pwm-pca9685-led.c diff --git a/Documentation/devicetree/bindings/pwm/nxp,pca9685-pwmled.txt b/Documentation/devicetree/bindings/pwm/nxp,pca9685-pwmled.txt new file mode 100644 index 0000000..16f11c8 --- /dev/null +++ b/Documentation/devicetree/bindings/pwm/nxp,pca9685-pwmled.txt @@ -0,0 +1,28 @@ +NXP PCA9685 16-channel 12-bit PWM LED controller +================================================ + +Required properties: + - compatible: "nxp,pca9685-pwmled" + - #pwm-cells: should be 2. The first cell specifies the per-chip index + of the PWM to use and the second cell is the period in nanoseconds. + The index 16 is the ALLCALL channel, that sets all pwm channels at the same + time. + +Optional properties: + - invrt: <0> output logic state not inverted + <1> output logic state inverted + - outdrv: <0> configure outputs with open-drain structure + <1> configure outputs with totem pole structure + +Example: + +For LEDs that are directly connected to the pca, the following setting is +applicable: + +pca: pca@41 { + compatible = "nx.,pca9685--pwmled"; + #pwm-cells = <2>; + reg = <0x41>; + invrt = <1>; + outdrv = <0>; +}; diff --git a/drivers/pwm/Kconfig b/drivers/pwm/Kconfig index 115b644..8696f61 100644 --- a/drivers/pwm/Kconfig +++ b/drivers/pwm/Kconfig @@ -97,6 +97,15 @@ config PWM_MXS To compile this driver as a module, choose M here: the module will be called pwm-mxs. +config PWM_PCA9685_LED + tristate "NXP PCA9685 PWM support for LED drivers" + depends on OF + help + Generic PWM framework driver for NXP PCA9685 LED controller. + + To compile this driver as a module, choose M here: the module + will be called pwm-pca9685-led. + config PWM_PUV3 tristate "PKUnity NetBook-0916 PWM support" depends on ARCH_PUV3 diff --git a/drivers/pwm/Makefile b/drivers/pwm/Makefile index 94ba21e..1924f03 100644 --- a/drivers/pwm/Makefile +++ b/drivers/pwm/Makefile @@ -6,6 +6,7 @@ obj-$(CONFIG_PWM_IMX) += pwm-imx.o obj-$(CONFIG_PWM_JZ4740) += pwm-jz4740.o obj-$(CONFIG_PWM_LPC32XX) += pwm-lpc32xx.o obj-$(CONFIG_PWM_MXS) += pwm-mxs.o +obj-$(CONFIG_PWM_PCA9685_LED) += pwm-pca9685-led.o obj-$(CONFIG_PWM_PUV3) += pwm-puv3.o obj-$(CONFIG_PWM_PXA) += pwm-pxa.o obj-$(CONFIG_PWM_SAMSUNG) += pwm-samsung.o diff --git a/drivers/pwm/pwm-pca9685-led.c b/drivers/pwm/pwm-pca9685-led.c new file mode 100644 index 0000000..c5e78b0 --- /dev/null +++ b/drivers/pwm/pwm-pca9685-led.c @@ -0,0 +1,245 @@ +/* + * Driver for PCA9685 16-channel 12-bit PWM LED controller + * + * Copyright (C) 2013 Steffen Trumtrar + * + * based on the pwm-twl-led.c driver + * + * This program is free software; you can redistribute it and/or modify it + * under the terms of the GNU General Public License version 2 as published by + * the Free Software Foundation. + * + * 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, see . + */ +#include +#include +#include +#include +#include +#include + +#define PCA9685_MODE1 0x00 +#define PCA9685_MODE2 0x01 +#define PCA9685_SUBADDR1 0x02 +#define PCA9685_SUBADDR2 0x03 +#define PCA9685_SUBADDR3 0x04 +#define PCA9685_ALLCALLADDR 0x05 +#define PCA9685_LEDX_ON_L 0x06 +#define PCA9685_LEDX_ON_H 0x07 +#define PCA9685_LEDX_OFF_L 0x08 +#define PCA9685_LEDX_OFF_H 0x09 + +#define PCA9685_ALL_LED_ON_L 0xFA +#define PCA9685_ALL_LED_ON_H 0xFB +#define PCA9685_ALL_LED_OFF_L 0xFC +#define PCA9685_ALL_LED_OFF_H 0xFD +#define PCA9685_PRESCALE 0xFE + +#define PCA9685_NUMREGS 0xFF +#define PCA9685_MAXCHAN 0x10 + +#define LED_FULL (1 << 4) +#define MODE1_SLEEP (1 << 4) +#define MODE2_INVRT (1 << 4) +#define MODE2_OUTDRV (1 << 2) + +#define LED_N_ON_H(N) (PCA9685_LEDX_ON_H + (4 * (N))) +#define LED_N_ON_L(N) (PCA9685_LEDX_ON_L + (4 * (N))) +#define LED_N_OFF_H(N) (PCA9685_LEDX_OFF_H + (4 * (N))) +#define LED_N_OFF_L(N) (PCA9685_LEDX_OFF_L + (4 * (N))) + +struct pca9685 { + struct pwm_chip chip; + struct regmap *regmap; + struct device *dev; +}; + +static inline struct pca9685 *to_pca(struct pwm_chip *chip) +{ + return container_of(chip, struct pca9685, chip); +} + +static int pca9685_pwmled_config(struct pwm_chip *chip, struct pwm_device *pwm, + int duty_ns, int period_ns) +{ + struct pca9685 *pca = to_pca(chip); + unsigned long long duty; + unsigned int reg; + + if (duty_ns < 1) + return 0; + + if (duty_ns == period_ns) { + reg = (pwm->hwpwm == PCA9685_MAXCHAN) ? PCA9685_ALL_LED_ON_H + : LED_N_ON_H(pwm->hwpwm); + regmap_write(pca->regmap, reg, LED_FULL); + return 0; + } + + duty = 4096 * (unsigned long long)duty_ns; + duty = DIV_ROUND_UP_ULL(duty, period_ns); + + reg = (pwm->hwpwm == PCA9685_MAXCHAN) ? PCA9685_ALL_LED_OFF_L + : LED_N_OFF_L(pwm->hwpwm); + regmap_write(pca->regmap, reg, 0xff & (int)duty); + reg = (pwm->hwpwm == PCA9685_MAXCHAN) ? PCA9685_ALL_LED_OFF_H + : LED_N_OFF_H(pwm->hwpwm); + regmap_write(pca->regmap, reg, 0xf & ((int)duty >> 8)); + + return 0; +} + +static int pca9685_pwmled_enable(struct pwm_chip *chip, struct pwm_device *pwm) +{ + struct pca9685 *pca = to_pca(chip); + unsigned int reg; + + /* the PWM subsystem does not support a pre-delay */ + reg = (pwm->hwpwm == PCA9685_MAXCHAN) ? PCA9685_ALL_LED_ON_L + : LED_N_ON_L(pwm->hwpwm); + regmap_write(pca->regmap, reg, 0); + reg = (pwm->hwpwm == PCA9685_MAXCHAN) ? PCA9685_ALL_LED_ON_H + : LED_N_ON_H(pwm->hwpwm); + regmap_write(pca->regmap, reg, 0); + + reg = (pwm->hwpwm == PCA9685_MAXCHAN) ? PCA9685_ALL_LED_OFF_H + : LED_N_OFF_H(pwm->hwpwm); + regmap_update_bits(pca->regmap, reg, LED_FULL, 0x0); + + return 0; +} + +static void pca9685_pwmled_disable(struct pwm_chip *chip, + struct pwm_device *pwm) +{ + struct pca9685 *pca = to_pca(chip); + unsigned int reg; + + reg = (pwm->hwpwm == PCA9685_MAXCHAN) ? PCA9685_ALL_LED_OFF_H + : LED_N_OFF_H(pwm->hwpwm); + regmap_write(pca->regmap, reg, LED_FULL); + reg = (pwm->hwpwm == PCA9685_MAXCHAN) ? PCA9685_ALL_LED_OFF_L + : LED_N_OFF_L(pwm->hwpwm); + regmap_write(pca->regmap, reg, 0x0); +} + +static int pca9685_pwmled_request(struct pwm_chip *chip, struct pwm_device *pwm) +{ + struct pca9685 *pca = to_pca(chip); + + return regmap_update_bits(pca->regmap, PCA9685_MODE1, MODE1_SLEEP, 0x0); +} + +static const struct pwm_ops pca9685_pwmled_ops = { + .enable = pca9685_pwmled_enable, + .disable = pca9685_pwmled_disable, + .config = pca9685_pwmled_config, + .request = pca9685_pwmled_request, +}; + +static struct regmap_config pca9685_regmap_i2c_config = { + .reg_bits = 8, + .val_bits = 8, + .max_register = PCA9685_NUMREGS, + .cache_type = REGCACHE_NONE, +}; + +static int pca9685_pwmled_probe(struct i2c_client *client, + const struct i2c_device_id *id) +{ + struct device_node *np = client->dev.of_node; + struct pca9685 *pca; + int ret; + int val; + int mode2; + + pca = devm_kzalloc(&client->dev, sizeof(*pca), GFP_KERNEL); + if (!pca) + return -ENOMEM; + + pca->regmap = devm_regmap_init_i2c(client, &pca9685_regmap_i2c_config); + if (IS_ERR(pca->regmap)) { + ret = PTR_ERR(pca->regmap); + dev_err(&client->dev, "Failed to initialize register map: %d\n", + ret); + return ret; + } + + i2c_set_clientdata(client, pca); + pca->dev = &client->dev; + + regmap_read(pca->regmap, PCA9685_MODE2, &mode2); + if (!of_property_read_u32(np, "invrt", &val)) { + if (val) + mode2 |= MODE2_INVRT; + else + mode2 &= ~MODE2_INVRT; + } + if (!of_property_read_u32(np, "outdrv", &val)) { + if (val) + mode2 |= MODE2_OUTDRV; + else + mode2 &= ~MODE2_OUTDRV; + } + regmap_write(pca->regmap, PCA9685_MODE2, mode2); + + /* clear all "full off" bits */ + regmap_write(pca->regmap, PCA9685_ALL_LED_OFF_L, 0); + regmap_write(pca->regmap, PCA9685_ALL_LED_OFF_H, 0); + + pca->chip.ops = &pca9685_pwmled_ops; + /* add an extra channel for ALL_LED */ + pca->chip.npwm = PCA9685_MAXCHAN + 1; + + pca->chip.dev = &client->dev; + pca->chip.base = -1; + pca->chip.can_sleep = true; + + ret = pwmchip_add(&pca->chip); + if (ret < 0) + return ret; + + return 0; +} + +static int pca9685_pwmled_remove(struct i2c_client *client) +{ + struct pca9685 *pca = i2c_get_clientdata(client); + + return pwmchip_remove(&pca->chip); +} + +static const struct i2c_device_id pca9685_id[] = { + {"pca9685", 0}, + {}, +}; +MODULE_DEVICE_TABLE(i2c, pca9685_id); + +static const struct of_device_id pca9685_dt_ids[] = { + { .compatible = "nxp,pca9685-pwmled", }, + { /* sentinel */ } +}; +MODULE_DEVICE_TABLE(of, pca9685_dt_ids); + +static struct i2c_driver pca9685_i2c_driver = { + .driver = { + .name = "pca9685", + .owner = THIS_MODULE, + .of_match_table = pca9685_dt_ids, + }, + .probe = pca9685_pwmled_probe, + .remove = pca9685_pwmled_remove, + .id_table = pca9685_id, +}; + +module_i2c_driver(pca9685_i2c_driver); + +MODULE_AUTHOR("Steffen Trumtrar "); +MODULE_DESCRIPTION("PWM driver for PCA9685 LED outputs"); +MODULE_LICENSE("GPL"); -- 1.8.2.rc2 -- 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/