From mboxrd@z Thu Jan 1 00:00:00 1970 From: stigge@antcom.de (Roland Stigge) Date: Wed, 07 Nov 2012 18:19:38 +0100 Subject: [PATCH] pwm: lpc32xx - Add a driver for the motor PWM In-Reply-To: <1352305828-25298-1-git-send-email-alban.bedel@avionic-design.de> References: <1352305828-25298-1-git-send-email-alban.bedel@avionic-design.de> Message-ID: <509A982A.6020401@antcom.de> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org On 07/11/12 17:30, Alban Bedel wrote: > Signed-off-by: Alban Bedel > --- > .../devicetree/bindings/pwm/lpc32xx-motor-pwm.txt | 24 ++ > arch/arm/boot/dts/lpc32xx.dtsi | 7 + Is all this supposed to go via mach-lpc32xx -> arm-soc.git? Then, I can take this into the lpc32xx tree. Otherwise, you can split off the .dtsi file and I include it via lpc32xx. Thanks, Roland > drivers/pwm/Kconfig | 10 + > drivers/pwm/Makefile | 1 + > drivers/pwm/pwm-lpc32xx-motor.c | 230 ++++++++++++++++++++ > 5 files changed, 272 insertions(+), 0 deletions(-) > create mode 100644 Documentation/devicetree/bindings/pwm/lpc32xx-motor-pwm.txt > create mode 100644 drivers/pwm/pwm-lpc32xx-motor.c > > diff --git a/Documentation/devicetree/bindings/pwm/lpc32xx-motor-pwm.txt b/Documentation/devicetree/bindings/pwm/lpc32xx-motor-pwm.txt > new file mode 100644 > index 0000000..e19b0a4 > --- /dev/null > +++ b/Documentation/devicetree/bindings/pwm/lpc32xx-motor-pwm.txt > @@ -0,0 +1,24 @@ > +LPC32XX Motor PWM controller > + > +The LPC32xx motor PWMs have two output pin, A and B, with B=!A. > +Per default the output A should be used, if the output B is used the > +PWM polarity should be inverted using the linux,polarity property. > + > +Required properties: > +- compatible: should be "nxp,lpc3220-motor-pwm" > +- reg: physical base address and length of the controller's registers > + > +Optional properites: > +- linux,polarity: Bit mask of the polarity to use for each output, > + a bit set to 0 indicate the default polarity, a bit set to 1 > + indicate an inverted polarity. In other word this set if output > + A or output B has the correct polarity. > + > +Examples: > + > +mpwm at 400e8000 { > + compatible = "nxp,lpc3220-motor-pwm"; > + reg = <0x400E8000 0x78>; > + linux,polarity = 5; /* Use outputs B0, A1 and B2 */ > + #pwm-cells = <2>; > +}; > diff --git a/arch/arm/boot/dts/lpc32xx.dtsi b/arch/arm/boot/dts/lpc32xx.dtsi > index ef0fdc7..a1e6a9b 100644 > --- a/arch/arm/boot/dts/lpc32xx.dtsi > +++ b/arch/arm/boot/dts/lpc32xx.dtsi > @@ -182,6 +182,13 @@ > pnx,timeout = <0x64>; > }; > > + mpwm: mpwm at 400E8000 { > + compatible = "nxp,lpc3220-motor-pwm"; > + reg = <0x400E8000 0x78>; > + status = "disabled"; > + #pwm-cells = <2>; > + }; > + > i2cusb: i2c at 31020300 { > compatible = "nxp,pnx-i2c"; > reg = <0x31020300 0x100>; > diff --git a/drivers/pwm/Kconfig b/drivers/pwm/Kconfig > index 90c5c73..90fc167 100644 > --- a/drivers/pwm/Kconfig > +++ b/drivers/pwm/Kconfig > @@ -57,6 +57,16 @@ config PWM_LPC32XX > To compile this driver as a module, choose M here: the module > will be called pwm-lpc32xx. > > +config PWM_LPC32XX_MOTOR > + tristate "LPC32XX Motor PWM support" > + depends on ARCH_LPC32XX > + help > + Generic PWM framework driver for LPC32XX motor PWM. The LPC32XX SOC > + has one motor PWM controllers. > + > + To compile this driver as a module, choose M here: the module > + will be called pwm-motor-lpc32xx. > + > config PWM_MXS > tristate "Freescale MXS PWM support" > depends on ARCH_MXS && OF > diff --git a/drivers/pwm/Makefile b/drivers/pwm/Makefile > index e4b2c89..510bad8 100644 > --- a/drivers/pwm/Makefile > +++ b/drivers/pwm/Makefile > @@ -2,6 +2,7 @@ obj-$(CONFIG_PWM) += core.o > obj-$(CONFIG_PWM_BFIN) += pwm-bfin.o > obj-$(CONFIG_PWM_IMX) += pwm-imx.o > obj-$(CONFIG_PWM_LPC32XX) += pwm-lpc32xx.o > +obj-$(CONFIG_PWM_LPC32XX_MOTOR) += pwm-lpc32xx-motor.o > obj-$(CONFIG_PWM_MXS) += pwm-mxs.o > obj-$(CONFIG_PWM_PXA) += pwm-pxa.o > obj-$(CONFIG_PWM_SAMSUNG) += pwm-samsung.o > diff --git a/drivers/pwm/pwm-lpc32xx-motor.c b/drivers/pwm/pwm-lpc32xx-motor.c > new file mode 100644 > index 0000000..e1b4d46 > --- /dev/null > +++ b/drivers/pwm/pwm-lpc32xx-motor.c > @@ -0,0 +1,230 @@ > +/* > + * Copyright 2012 Alban Bedel > + * > + * Based on pwm-lpc32xx.c from Alexandre Pereira da Silva > + * > + * > + * 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; version 2. > + * > + */ > + > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > +#include > + > +struct lpc32xx_motor_pwm_chip { > + struct pwm_chip chip; > + struct clk *clk; > + spinlock_t lock; > + unsigned int clk_enabled; > + unsigned int pins; > + void __iomem *base; > +}; > + > +#define to_lpc32xx_motor_pwm_chip(_chip) \ > + container_of(_chip, struct lpc32xx_motor_pwm_chip, chip) > + > +/* Register mapping for MCPWM modules */ > +#define LPC32XX_MCPWM_MCCON 0x00 > +#define LPC32XX_MCPWM_MCCON_SET 0x04 > +#define LPC32XX_MCPWM_MCCON_CLR 0x08 > +#define LPC32XX_MCPWM_MCCAPCON 0x0C > +#define LPC32XX_MCPWM_MCCAPCON_SET 0x10 > +#define LPC32XX_MCPWM_MCCAPCON_CLR 0x14 > +#define LPC32XX_MCPWM_MCLIM0 0x24 > +#define LPC32XX_MCPWM_MCLIM1 0x28 > +#define LPC32XX_MCPWM_MCLIM2 0x2C > +#define LPC32XX_MCPWM_MCMAT0 0x30 > +#define LPC32XX_MCPWM_MCMAT1 0x34 > +#define LPC32XX_MCPWM_MCMAT2 0x38 > +#define LPC32XX_MCPWM_MCINTEN_CLR 0x58 > + > +#define LPC32XX_MCPWM_COUNT 3 > + > +#define PWM_EN_MASK(pwm) BIT(0 + (pwm)->hwpwm*8) > +#define MCLIM_REG_OFFSET(pwm) (LPC32XX_MCPWM_MCLIM0 + (pwm)->hwpwm*4) > +#define MCMAT_REG_OFFSET(pwm) (LPC32XX_MCPWM_MCMAT0 + (pwm)->hwpwm*4) > + > +static int lpc32xx_motor_pwm_enable_clock( > + struct lpc32xx_motor_pwm_chip *lpc32xx) > +{ > + int err = 0; > + spin_lock(&lpc32xx->lock); > + if (lpc32xx->clk_enabled == 0) > + err = clk_enable(lpc32xx->clk); > + lpc32xx->clk_enabled += 1; > + spin_unlock(&lpc32xx->lock); > + return err; > +} > + > +static void lpc32xx_motor_pwm_disable_clock( > + struct lpc32xx_motor_pwm_chip *lpc32xx) > +{ > + spin_lock(&lpc32xx->lock); > + if (lpc32xx->clk_enabled > 0) { > + lpc32xx->clk_enabled -= 1; > + if (lpc32xx->clk_enabled == 0) > + clk_disable(lpc32xx->clk); > + } > + spin_unlock(&lpc32xx->lock); > +} > + > +static int lpc32xx_motor_pwm_config(struct pwm_chip *chip, > + struct pwm_device *pwm, > + int duty_ns, int period_ns) > +{ > + struct lpc32xx_motor_pwm_chip *lpc32xx = > + to_lpc32xx_motor_pwm_chip(chip); > + u64 rate, per, duty; > + int err = 0; > + > + /* The clock is needed to access the registers */ > + err = lpc32xx_motor_pwm_enable_clock(lpc32xx); > + if (err) > + return err; > + > + /* Calculate period */ > + rate = clk_get_rate(lpc32xx->clk); > + per = (u64)period_ns * rate; > + duty = (u64)duty_ns * rate; > + do_div(per, 1000000000); > + do_div(duty, 1000000000); > + > + /* Write to limit register -> period */ > + __raw_writel(per, lpc32xx->base + MCLIM_REG_OFFSET(pwm)); > + > + /* Write to match register -> duty */ > + __raw_writel(per - duty, lpc32xx->base + MCMAT_REG_OFFSET(pwm)); > + > + /* Disable the clock now that we are done */ > + lpc32xx_motor_pwm_disable_clock(lpc32xx); > + return 0; > +} > + > +static int lpc32xx_motor_pwm_enable(struct pwm_chip *chip, > + struct pwm_device *pwm) > +{ > + struct lpc32xx_motor_pwm_chip *lpc32xx = > + to_lpc32xx_motor_pwm_chip(chip); > + int err; > + > + err = lpc32xx_motor_pwm_enable_clock(lpc32xx); > + if (err) > + return err; > + > + __raw_writel(PWM_EN_MASK(pwm), lpc32xx->base + LPC32XX_MCPWM_MCCON_SET); > + > + return 0; > +} > + > +static void lpc32xx_motor_pwm_disable(struct pwm_chip *chip, > + struct pwm_device *pwm) > +{ > + struct lpc32xx_motor_pwm_chip *lpc32xx = > + to_lpc32xx_motor_pwm_chip(chip); > + > + __raw_writel(PWM_EN_MASK(pwm), lpc32xx->base + LPC32XX_MCPWM_MCCON_CLR); > + > + lpc32xx_motor_pwm_disable_clock(lpc32xx); > +} > + > +static const struct pwm_ops lpc32xx_motor_pwm_ops = { > + .config = lpc32xx_motor_pwm_config, > + .enable = lpc32xx_motor_pwm_enable, > + .disable = lpc32xx_motor_pwm_disable, > + .owner = THIS_MODULE, > +}; > + > +static int lpc32xx_motor_pwm_probe(struct platform_device *pdev) > +{ > + struct lpc32xx_motor_pwm_chip *lpc32xx; > + struct resource *res; > + int ret; > + > + lpc32xx = devm_kzalloc(&pdev->dev, sizeof(*lpc32xx), GFP_KERNEL); > + if (!lpc32xx) > + return -ENOMEM; > + > + res = platform_get_resource(pdev, IORESOURCE_MEM, 0); > + if (!res) > + return -EINVAL; > + > + lpc32xx->base = devm_request_and_ioremap(&pdev->dev, res); > + if (!lpc32xx->base) > + return -EADDRNOTAVAIL; > + > + lpc32xx->clk = devm_clk_get(&pdev->dev, NULL); > + if (IS_ERR(lpc32xx->clk)) > + return PTR_ERR(lpc32xx->clk); > + > + spin_lock_init(&lpc32xx->lock); > + > + /* Configure the pins polarity */ > + ret = of_property_read_u32(pdev->dev.of_node, "linux,polarity", > + &lpc32xx->pins); > + if (!ret) { > + u32 set = 0, clr = 0; > + int i; > + for (i = 0 ; i < LPC32XX_MCPWM_COUNT ; i += 1) > + if (lpc32xx->pins & BIT(i)) > + set |= BIT(2 + i*8); > + else > + clr |= BIT(2 + i*8); > + __raw_writel(set, lpc32xx->base + LPC32XX_MCPWM_MCCON_SET); > + __raw_writel(clr, lpc32xx->base + LPC32XX_MCPWM_MCCON_CLR); > + } > + > + lpc32xx->chip.dev = &pdev->dev; > + lpc32xx->chip.ops = &lpc32xx_motor_pwm_ops; > + lpc32xx->chip.npwm = LPC32XX_MCPWM_COUNT; > + lpc32xx->chip.base = -1; > + > + ret = pwmchip_add(&lpc32xx->chip); > + if (ret < 0) { > + dev_err(&pdev->dev, "failed to add PWM chip, error %d\n", ret); > + return ret; > + } > + > + platform_set_drvdata(pdev, lpc32xx); > + > + return 0; > +} > + > +static int __devexit lpc32xx_motor_pwm_remove(struct platform_device *pdev) > +{ > + struct lpc32xx_motor_pwm_chip *lpc32xx = platform_get_drvdata(pdev); > + > + clk_disable(lpc32xx->clk); > + return pwmchip_remove(&lpc32xx->chip); > +} > + > +static const struct of_device_id lpc32xx_motor_pwm_dt_ids[] __devinitconst = { > + { .compatible = "nxp,lpc3220-motor-pwm", }, > + { /* sentinel */ } > +}; > +MODULE_DEVICE_TABLE(of, lpc32xx_motor_pwm_dt_ids); > + > +static struct platform_driver lpc32xx_motor_pwm_driver = { > + .driver = { > + .name = "lpc32xx-motor-pwm", > + .owner = THIS_MODULE, > + .of_match_table = of_match_ptr(lpc32xx_motor_pwm_dt_ids), > + }, > + .probe = lpc32xx_motor_pwm_probe, > + .remove = __devexit_p(lpc32xx_motor_pwm_remove), > +}; > +module_platform_driver(lpc32xx_motor_pwm_driver); > + > +MODULE_ALIAS("platform:lpc32xx-motor-pwm"); > +MODULE_AUTHOR("Alban Bedel "); > +MODULE_DESCRIPTION("LPC32XX Motor PWM Driver"); > +MODULE_LICENSE("GPL v2");