From 6f5941c93bdf7649f392f1263b9068d360ceab4d Mon Sep 17 00:00:00 2001 From: John Crispin Date: Fri, 6 May 2016 02:55:48 +0200 Subject: [PATCH 071/102] pwm: add pwm-mediatek Signed-off-by: John Crispin --- arch/arm/boot/dts/mt7623-evb.dts | 17 +++ arch/arm/boot/dts/mt7623.dtsi | 22 ++++ drivers/pwm/Kconfig | 9 ++ drivers/pwm/Makefile | 1 + drivers/pwm/pwm-mediatek.c | 230 ++++++++++++++++++++++++++++++++++++++ 5 files changed, 279 insertions(+) create mode 100644 drivers/pwm/pwm-mediatek.c --- a/drivers/pwm/Kconfig +++ b/drivers/pwm/Kconfig @@ -282,6 +282,15 @@ config PWM_MTK_DISP To compile this driver as a module, choose M here: the module will be called pwm-mtk-disp. +config PWM_MEDIATEK + tristate "MediaTek PWM support" + depends on ARCH_MEDIATEK || COMPILE_TEST + help + Generic PWM framework driver for Mediatek ARM SoC. + + To compile this driver as a module, choose M here: the module + will be called pwm-mxs. + config PWM_MXS tristate "Freescale MXS PWM support" depends on ARCH_MXS && OF --- a/drivers/pwm/Makefile +++ b/drivers/pwm/Makefile @@ -25,6 +25,7 @@ obj-$(CONFIG_PWM_LPSS) += pwm-lpss.o obj-$(CONFIG_PWM_LPSS_PCI) += pwm-lpss-pci.o obj-$(CONFIG_PWM_LPSS_PLATFORM) += pwm-lpss-platform.o obj-$(CONFIG_PWM_MESON) += pwm-meson.o +obj-$(CONFIG_PWM_MEDIATEK) += pwm-mediatek.o obj-$(CONFIG_PWM_MTK_DISP) += pwm-mtk-disp.o obj-$(CONFIG_PWM_MXS) += pwm-mxs.o obj-$(CONFIG_PWM_OMAP_DMTIMER) += pwm-omap-dmtimer.o --- /dev/null +++ b/drivers/pwm/pwm-mediatek.c @@ -0,0 +1,230 @@ +/* + * Mediatek Pulse Width Modulator driver + * + * Copyright (C) 2015 John Crispin + * + * This file is licensed under the terms of the GNU General Public + * License version 2. This program is licensed "as is" without any + * warranty of any kind, whether express or implied. + */ + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#define NUM_PWM 5 + +/* PWM registers and bits definitions */ +#define PWMCON 0x00 +#define PWMHDUR 0x04 +#define PWMLDUR 0x08 +#define PWMGDUR 0x0c +#define PWMWAVENUM 0x28 +#define PWMDWIDTH 0x2c +#define PWMTHRES 0x30 + +/** + * struct mtk_pwm_chip - struct representing pwm chip + * + * @mmio_base: base address of pwm chip + * @chip: linux pwm chip representation + */ +struct mtk_pwm_chip { + void __iomem *mmio_base; + struct pwm_chip chip; + struct clk *clk_top; + struct clk *clk_main; + struct clk *clk_pwm[NUM_PWM]; +}; + +static inline struct mtk_pwm_chip *to_mtk_pwm_chip(struct pwm_chip *chip) +{ + return container_of(chip, struct mtk_pwm_chip, chip); +} + +static inline u32 mtk_pwm_readl(struct mtk_pwm_chip *chip, unsigned int num, + unsigned long offset) +{ + return ioread32(chip->mmio_base + 0x10 + (num * 0x40) + offset); +} + +static inline void mtk_pwm_writel(struct mtk_pwm_chip *chip, + unsigned int num, unsigned long offset, + unsigned long val) +{ + iowrite32(val, chip->mmio_base + 0x10 + (num * 0x40) + offset); +} + +static int mtk_pwm_config(struct pwm_chip *chip, struct pwm_device *pwm, + int duty_ns, int period_ns) +{ + struct mtk_pwm_chip *pc = to_mtk_pwm_chip(chip); + u32 resolution = 100 / 4; + u32 clkdiv = 0; + + resolution = 1000000000 / (clk_get_rate(pc->clk_pwm[pwm->hwpwm])); + + while (period_ns / resolution > 8191) { + clkdiv++; + resolution *= 2; + } + + if (clkdiv > 7) + return -1; + + mtk_pwm_writel(pc, pwm->hwpwm, PWMCON, BIT(15) | BIT(3) | clkdiv); + mtk_pwm_writel(pc, pwm->hwpwm, PWMDWIDTH, period_ns / resolution); + mtk_pwm_writel(pc, pwm->hwpwm, PWMTHRES, duty_ns / resolution); + return 0; +} + +static int mtk_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm) +{ + struct mtk_pwm_chip *pc = to_mtk_pwm_chip(chip); + u32 val; + int ret; + + ret = clk_prepare(pc->clk_pwm[pwm->hwpwm]); + if (ret < 0) + return ret; + + val = ioread32(pc->mmio_base); + val |= BIT(pwm->hwpwm); + iowrite32(val, pc->mmio_base); + + return 0; +} + +static void mtk_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm) +{ + struct mtk_pwm_chip *pc = to_mtk_pwm_chip(chip); + u32 val; + + val = ioread32(pc->mmio_base); + val &= ~BIT(pwm->hwpwm); + iowrite32(val, pc->mmio_base); + clk_unprepare(pc->clk_pwm[pwm->hwpwm]); +} + +static const struct pwm_ops mtk_pwm_ops = { + .config = mtk_pwm_config, + .enable = mtk_pwm_enable, + .disable = mtk_pwm_disable, + .owner = THIS_MODULE, +}; + +static int mtk_pwm_probe(struct platform_device *pdev) +{ + struct mtk_pwm_chip *pc; + struct resource *r; + int ret; + + pc = devm_kzalloc(&pdev->dev, sizeof(*pc), GFP_KERNEL); + if (!pc) + return -ENOMEM; + + r = platform_get_resource(pdev, IORESOURCE_MEM, 0); + pc->mmio_base = devm_ioremap_resource(&pdev->dev, r); + if (IS_ERR(pc->mmio_base)) + return PTR_ERR(pc->mmio_base); + + pc->clk_main = devm_clk_get(&pdev->dev, "main"); + if (IS_ERR(pc->clk_main)) + return PTR_ERR(pc->clk_main); + + pc->clk_top = devm_clk_get(&pdev->dev, "top"); + if (IS_ERR(pc->clk_top)) + return PTR_ERR(pc->clk_top); + + pc->clk_pwm[0] = devm_clk_get(&pdev->dev, "pwm1"); + if (IS_ERR(pc->clk_pwm[0])) + return PTR_ERR(pc->clk_pwm[0]); + + pc->clk_pwm[1] = devm_clk_get(&pdev->dev, "pwm2"); + if (IS_ERR(pc->clk_pwm[1])) + return PTR_ERR(pc->clk_pwm[1]); + + pc->clk_pwm[2] = devm_clk_get(&pdev->dev, "pwm3"); + if (IS_ERR(pc->clk_pwm[2])) + return PTR_ERR(pc->clk_pwm[2]); + + pc->clk_pwm[3] = devm_clk_get(&pdev->dev, "pwm4"); + if (IS_ERR(pc->clk_pwm[3])) + return PTR_ERR(pc->clk_pwm[3]); + + pc->clk_pwm[4] = devm_clk_get(&pdev->dev, "pwm5"); + if (IS_ERR(pc->clk_pwm[4])) + return PTR_ERR(pc->clk_pwm[4]); + + ret = clk_prepare(pc->clk_top); + if (ret < 0) + return ret; + + ret = clk_prepare(pc->clk_main); + if (ret < 0) + goto disable_clk_top; + + platform_set_drvdata(pdev, pc); + + pc->chip.dev = &pdev->dev; + pc->chip.ops = &mtk_pwm_ops; + pc->chip.base = -1; + pc->chip.npwm = NUM_PWM; + + ret = pwmchip_add(&pc->chip); + if (ret < 0) { + dev_err(&pdev->dev, "pwmchip_add() failed: %d\n", ret); + goto disable_clk_main; + } + + return 0; + +disable_clk_main: + clk_unprepare(pc->clk_main); +disable_clk_top: + clk_unprepare(pc->clk_top); + + return ret; +} + +static int mtk_pwm_remove(struct platform_device *pdev) +{ + struct mtk_pwm_chip *pc = platform_get_drvdata(pdev); + int i; + + for (i = 0; i < NUM_PWM; i++) + pwm_disable(&pc->chip.pwms[i]); + + return pwmchip_remove(&pc->chip); +} + +static const struct of_device_id mtk_pwm_of_match[] = { + { .compatible = "mediatek,mt7623-pwm" }, + { } +}; + +MODULE_DEVICE_TABLE(of, mtk_pwm_of_match); + +static struct platform_driver mtk_pwm_driver = { + .driver = { + .name = "mtk-pwm", + .owner = THIS_MODULE, + .of_match_table = mtk_pwm_of_match, + }, + .probe = mtk_pwm_probe, + .remove = mtk_pwm_remove, +}; + +module_platform_driver(mtk_pwm_driver); + +MODULE_LICENSE("GPL"); +MODULE_AUTHOR("John Crispin "); +MODULE_ALIAS("platform:mtk-pwm");