| /* |
| * Mediatek Pulse Width Modulator driver |
| * |
| * Copyright (C) 2015 John Crispin <blogic@openwrt.org> |
| * Copyright (C) 2017 Zhi Mao <zhi.mao@mediatek.com> |
| * |
| * 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 <linux/err.h> |
| #include <linux/io.h> |
| #include <linux/ioport.h> |
| #include <linux/kernel.h> |
| #include <linux/module.h> |
| #include <linux/clk.h> |
| #include <linux/of.h> |
| #include <linux/of_device.h> |
| #include <linux/platform_device.h> |
| #include <linux/pwm.h> |
| #include <linux/slab.h> |
| #include <linux/types.h> |
| |
| /* PWM registers and bits definitions */ |
| #define PWMCON 0x00 |
| #define PWMHDUR 0x04 |
| #define PWMLDUR 0x08 |
| #define PWMGDUR 0x0c |
| #define PWMWAVENUM 0x28 |
| #define PWMDWIDTH 0x2c |
| #define PWM45DWIDTH_FIXUP 0x30 |
| #define PWMTHRES 0x30 |
| #define PWM45THRES_FIXUP 0x34 |
| |
| #define PWM_CLK_DIV_MAX 7 |
| |
| enum { |
| MTK_CLK_MAIN = 0, |
| MTK_CLK_TOP, |
| MTK_CLK_PWM1, |
| MTK_CLK_PWM2, |
| MTK_CLK_PWM3, |
| MTK_CLK_PWM4, |
| MTK_CLK_PWM5, |
| MTK_CLK_PWM6, |
| MTK_CLK_PWM7, |
| MTK_CLK_PWM8, |
| MTK_CLK_MAX, |
| }; |
| |
| static const char * const mtk_pwm_clk_name[MTK_CLK_MAX] = { |
| "main", "top", "pwm1", "pwm2", "pwm3", "pwm4", "pwm5", "pwm6", "pwm7", |
| "pwm8" |
| }; |
| |
| struct mtk_pwm_platform_data { |
| unsigned int num_pwms; |
| bool pwm45_fixup; |
| bool has_clks; |
| }; |
| |
| /** |
| * struct mtk_pwm_chip - struct representing PWM chip |
| * @chip: linux PWM chip representation |
| * @regs: base address of PWM chip |
| * @clks: list of clocks |
| */ |
| struct mtk_pwm_chip { |
| struct pwm_chip chip; |
| void __iomem *regs; |
| struct clk *clks[MTK_CLK_MAX]; |
| const struct mtk_pwm_platform_data *soc; |
| }; |
| |
| static const unsigned int mtk_pwm_reg_offset[] = { |
| 0x0010, 0x0050, 0x0090, 0x00d0, 0x0110, 0x0150, 0x0190, 0x0220 |
| }; |
| |
| static inline struct mtk_pwm_chip *to_mtk_pwm_chip(struct pwm_chip *chip) |
| { |
| return container_of(chip, struct mtk_pwm_chip, chip); |
| } |
| |
| static int mtk_pwm_clk_enable(struct pwm_chip *chip, struct pwm_device *pwm) |
| { |
| struct mtk_pwm_chip *pc = to_mtk_pwm_chip(chip); |
| int ret; |
| |
| if (!pc->soc->has_clks) |
| return 0; |
| |
| ret = clk_prepare_enable(pc->clks[MTK_CLK_TOP]); |
| if (ret < 0) |
| return ret; |
| |
| ret = clk_prepare_enable(pc->clks[MTK_CLK_MAIN]); |
| if (ret < 0) |
| goto disable_clk_top; |
| |
| ret = clk_prepare_enable(pc->clks[MTK_CLK_PWM1 + pwm->hwpwm]); |
| if (ret < 0) |
| goto disable_clk_main; |
| |
| return 0; |
| |
| disable_clk_main: |
| clk_disable_unprepare(pc->clks[MTK_CLK_MAIN]); |
| disable_clk_top: |
| clk_disable_unprepare(pc->clks[MTK_CLK_TOP]); |
| |
| return ret; |
| } |
| |
| static void mtk_pwm_clk_disable(struct pwm_chip *chip, struct pwm_device *pwm) |
| { |
| struct mtk_pwm_chip *pc = to_mtk_pwm_chip(chip); |
| |
| if (!pc->soc->has_clks) |
| return; |
| |
| clk_disable_unprepare(pc->clks[MTK_CLK_PWM1 + pwm->hwpwm]); |
| clk_disable_unprepare(pc->clks[MTK_CLK_MAIN]); |
| clk_disable_unprepare(pc->clks[MTK_CLK_TOP]); |
| } |
| |
| static inline u32 mtk_pwm_readl(struct mtk_pwm_chip *chip, unsigned int num, |
| unsigned int offset) |
| { |
| return readl(chip->regs + mtk_pwm_reg_offset[num] + offset); |
| } |
| |
| static inline void mtk_pwm_writel(struct mtk_pwm_chip *chip, |
| unsigned int num, unsigned int offset, |
| u32 value) |
| { |
| writel(value, chip->regs + mtk_pwm_reg_offset[num] + 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); |
| struct clk *clk = pc->clks[MTK_CLK_PWM1 + pwm->hwpwm]; |
| u32 clkdiv = 0, cnt_period, cnt_duty, reg_width = PWMDWIDTH, |
| reg_thres = PWMTHRES; |
| u64 resolution; |
| int ret; |
| |
| ret = mtk_pwm_clk_enable(chip, pwm); |
| if (ret < 0) |
| return ret; |
| |
| /* Using resolution in picosecond gets accuracy higher */ |
| resolution = (u64)NSEC_PER_SEC * 1000; |
| do_div(resolution, clk_get_rate(clk)); |
| |
| cnt_period = DIV_ROUND_CLOSEST_ULL((u64)period_ns * 1000, resolution); |
| while (cnt_period > 8191) { |
| resolution *= 2; |
| clkdiv++; |
| cnt_period = DIV_ROUND_CLOSEST_ULL((u64)period_ns * 1000, |
| resolution); |
| } |
| |
| if (clkdiv > PWM_CLK_DIV_MAX) { |
| mtk_pwm_clk_disable(chip, pwm); |
| dev_err(chip->dev, "period %d not supported\n", period_ns); |
| return -EINVAL; |
| } |
| |
| if (pc->soc->pwm45_fixup && pwm->hwpwm > 2) { |
| /* |
| * PWM[4,5] has distinct offset for PWMDWIDTH and PWMTHRES |
| * from the other PWMs on MT7623. |
| */ |
| reg_width = PWM45DWIDTH_FIXUP; |
| reg_thres = PWM45THRES_FIXUP; |
| } |
| |
| cnt_duty = DIV_ROUND_CLOSEST_ULL((u64)duty_ns * 1000, resolution); |
| mtk_pwm_writel(pc, pwm->hwpwm, PWMCON, BIT(15) | clkdiv); |
| mtk_pwm_writel(pc, pwm->hwpwm, reg_width, cnt_period); |
| mtk_pwm_writel(pc, pwm->hwpwm, reg_thres, cnt_duty); |
| |
| mtk_pwm_clk_disable(chip, pwm); |
| |
| 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 value; |
| int ret; |
| |
| ret = mtk_pwm_clk_enable(chip, pwm); |
| if (ret < 0) |
| return ret; |
| |
| value = readl(pc->regs); |
| value |= BIT(pwm->hwpwm); |
| writel(value, pc->regs); |
| |
| 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 value; |
| |
| value = readl(pc->regs); |
| value &= ~BIT(pwm->hwpwm); |
| writel(value, pc->regs); |
| |
| mtk_pwm_clk_disable(chip, pwm); |
| } |
| |
| 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) |
| { |
| const struct mtk_pwm_platform_data *data; |
| struct mtk_pwm_chip *pc; |
| struct resource *res; |
| unsigned int i; |
| int ret; |
| |
| pc = devm_kzalloc(&pdev->dev, sizeof(*pc), GFP_KERNEL); |
| if (!pc) |
| return -ENOMEM; |
| |
| data = of_device_get_match_data(&pdev->dev); |
| if (data == NULL) |
| return -EINVAL; |
| pc->soc = data; |
| |
| res = platform_get_resource(pdev, IORESOURCE_MEM, 0); |
| pc->regs = devm_ioremap_resource(&pdev->dev, res); |
| if (IS_ERR(pc->regs)) |
| return PTR_ERR(pc->regs); |
| |
| for (i = 0; i < data->num_pwms + 2 && pc->soc->has_clks; i++) { |
| pc->clks[i] = devm_clk_get(&pdev->dev, mtk_pwm_clk_name[i]); |
| if (IS_ERR(pc->clks[i])) { |
| dev_err(&pdev->dev, "clock: %s fail: %ld\n", |
| mtk_pwm_clk_name[i], PTR_ERR(pc->clks[i])); |
| return PTR_ERR(pc->clks[i]); |
| } |
| } |
| |
| platform_set_drvdata(pdev, pc); |
| |
| pc->chip.dev = &pdev->dev; |
| pc->chip.ops = &mtk_pwm_ops; |
| pc->chip.base = -1; |
| pc->chip.npwm = data->num_pwms; |
| |
| ret = pwmchip_add(&pc->chip); |
| if (ret < 0) { |
| dev_err(&pdev->dev, "pwmchip_add() failed: %d\n", ret); |
| return ret; |
| } |
| |
| return 0; |
| } |
| |
| static int mtk_pwm_remove(struct platform_device *pdev) |
| { |
| struct mtk_pwm_chip *pc = platform_get_drvdata(pdev); |
| |
| return pwmchip_remove(&pc->chip); |
| } |
| |
| static const struct mtk_pwm_platform_data mt6880_pwm_data = { |
| .num_pwms = 7, |
| .pwm45_fixup = false, |
| .has_clks = true, |
| }; |
| |
| static const struct mtk_pwm_platform_data mt2712_pwm_data = { |
| .num_pwms = 8, |
| .pwm45_fixup = false, |
| .has_clks = true, |
| }; |
| |
| static const struct mtk_pwm_platform_data mt7622_pwm_data = { |
| .num_pwms = 6, |
| .pwm45_fixup = false, |
| .has_clks = true, |
| }; |
| |
| static const struct mtk_pwm_platform_data mt7623_pwm_data = { |
| .num_pwms = 5, |
| .pwm45_fixup = true, |
| .has_clks = true, |
| }; |
| |
| static const struct mtk_pwm_platform_data mt7628_pwm_data = { |
| .num_pwms = 4, |
| .pwm45_fixup = true, |
| .has_clks = false, |
| }; |
| |
| static const struct of_device_id mtk_pwm_of_match[] = { |
| { .compatible = "mediatek,mt6880-pwm", .data = &mt6880_pwm_data }, |
| { .compatible = "mediatek,mt2712-pwm", .data = &mt2712_pwm_data }, |
| { .compatible = "mediatek,mt7622-pwm", .data = &mt7622_pwm_data }, |
| { .compatible = "mediatek,mt7623-pwm", .data = &mt7623_pwm_data }, |
| { .compatible = "mediatek,mt7628-pwm", .data = &mt7628_pwm_data }, |
| { }, |
| }; |
| MODULE_DEVICE_TABLE(of, mtk_pwm_of_match); |
| |
| static struct platform_driver mtk_pwm_driver = { |
| .driver = { |
| .name = "mtk-pwm", |
| .of_match_table = mtk_pwm_of_match, |
| }, |
| .probe = mtk_pwm_probe, |
| .remove = mtk_pwm_remove, |
| }; |
| module_platform_driver(mtk_pwm_driver); |
| |
| MODULE_AUTHOR("John Crispin <blogic@openwrt.org>"); |
| MODULE_LICENSE("GPL"); |