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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
commit | 2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch) | |
tree | 848558de17fb3008cdf4d861b01ac7781903ce39 /drivers/pwm/pwm-mtk-disp.c | |
parent | Initial commit. (diff) | |
download | linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip |
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'drivers/pwm/pwm-mtk-disp.c')
-rw-r--r-- | drivers/pwm/pwm-mtk-disp.c | 332 |
1 files changed, 332 insertions, 0 deletions
diff --git a/drivers/pwm/pwm-mtk-disp.c b/drivers/pwm/pwm-mtk-disp.c new file mode 100644 index 000000000..db286284f --- /dev/null +++ b/drivers/pwm/pwm-mtk-disp.c @@ -0,0 +1,332 @@ +// SPDX-License-Identifier: GPL-2.0-only +/* + * MediaTek display pulse-width-modulation controller driver. + * Copyright (c) 2015 MediaTek Inc. + * Author: YH Huang <yh.huang@mediatek.com> + */ + +#include <linux/bitfield.h> +#include <linux/clk.h> +#include <linux/err.h> +#include <linux/io.h> +#include <linux/module.h> +#include <linux/of.h> +#include <linux/of_device.h> +#include <linux/platform_device.h> +#include <linux/pwm.h> +#include <linux/slab.h> + +#define DISP_PWM_EN 0x00 + +#define PWM_CLKDIV_SHIFT 16 +#define PWM_CLKDIV_MAX 0x3ff +#define PWM_CLKDIV_MASK (PWM_CLKDIV_MAX << PWM_CLKDIV_SHIFT) + +#define PWM_PERIOD_BIT_WIDTH 12 +#define PWM_PERIOD_MASK ((1 << PWM_PERIOD_BIT_WIDTH) - 1) + +#define PWM_HIGH_WIDTH_SHIFT 16 +#define PWM_HIGH_WIDTH_MASK (0x1fff << PWM_HIGH_WIDTH_SHIFT) + +struct mtk_pwm_data { + u32 enable_mask; + unsigned int con0; + u32 con0_sel; + unsigned int con1; + + bool has_commit; + unsigned int commit; + unsigned int commit_mask; + + unsigned int bls_debug; + u32 bls_debug_mask; +}; + +struct mtk_disp_pwm { + struct pwm_chip chip; + const struct mtk_pwm_data *data; + struct clk *clk_main; + struct clk *clk_mm; + void __iomem *base; + bool enabled; +}; + +static inline struct mtk_disp_pwm *to_mtk_disp_pwm(struct pwm_chip *chip) +{ + return container_of(chip, struct mtk_disp_pwm, chip); +} + +static void mtk_disp_pwm_update_bits(struct mtk_disp_pwm *mdp, u32 offset, + u32 mask, u32 data) +{ + void __iomem *address = mdp->base + offset; + u32 value; + + value = readl(address); + value &= ~mask; + value |= data; + writel(value, address); +} + +static int mtk_disp_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm, + const struct pwm_state *state) +{ + struct mtk_disp_pwm *mdp = to_mtk_disp_pwm(chip); + u32 clk_div, period, high_width, value; + u64 div, rate; + int err; + + if (state->polarity != PWM_POLARITY_NORMAL) + return -EINVAL; + + if (!state->enabled && mdp->enabled) { + mtk_disp_pwm_update_bits(mdp, DISP_PWM_EN, + mdp->data->enable_mask, 0x0); + clk_disable_unprepare(mdp->clk_mm); + clk_disable_unprepare(mdp->clk_main); + + mdp->enabled = false; + return 0; + } + + if (!mdp->enabled) { + err = clk_prepare_enable(mdp->clk_main); + if (err < 0) { + dev_err(chip->dev, "Can't enable mdp->clk_main: %pe\n", + ERR_PTR(err)); + return err; + } + + err = clk_prepare_enable(mdp->clk_mm); + if (err < 0) { + dev_err(chip->dev, "Can't enable mdp->clk_mm: %pe\n", + ERR_PTR(err)); + clk_disable_unprepare(mdp->clk_main); + return err; + } + } + + /* + * Find period, high_width and clk_div to suit duty_ns and period_ns. + * Calculate proper div value to keep period value in the bound. + * + * period_ns = 10^9 * (clk_div + 1) * (period + 1) / PWM_CLK_RATE + * duty_ns = 10^9 * (clk_div + 1) * high_width / PWM_CLK_RATE + * + * period = (PWM_CLK_RATE * period_ns) / (10^9 * (clk_div + 1)) - 1 + * high_width = (PWM_CLK_RATE * duty_ns) / (10^9 * (clk_div + 1)) + */ + rate = clk_get_rate(mdp->clk_main); + clk_div = mul_u64_u64_div_u64(state->period, rate, NSEC_PER_SEC) >> + PWM_PERIOD_BIT_WIDTH; + if (clk_div > PWM_CLKDIV_MAX) { + if (!mdp->enabled) { + clk_disable_unprepare(mdp->clk_mm); + clk_disable_unprepare(mdp->clk_main); + } + return -EINVAL; + } + + div = NSEC_PER_SEC * (clk_div + 1); + period = mul_u64_u64_div_u64(state->period, rate, div); + if (period > 0) + period--; + + high_width = mul_u64_u64_div_u64(state->duty_cycle, rate, div); + value = period | (high_width << PWM_HIGH_WIDTH_SHIFT); + + if (mdp->data->bls_debug && !mdp->data->has_commit) { + /* + * For MT2701, disable double buffer before writing register + * and select manual mode and use PWM_PERIOD/PWM_HIGH_WIDTH. + */ + mtk_disp_pwm_update_bits(mdp, mdp->data->bls_debug, + mdp->data->bls_debug_mask, + mdp->data->bls_debug_mask); + mtk_disp_pwm_update_bits(mdp, mdp->data->con0, + mdp->data->con0_sel, + mdp->data->con0_sel); + } + + mtk_disp_pwm_update_bits(mdp, mdp->data->con0, + PWM_CLKDIV_MASK, + clk_div << PWM_CLKDIV_SHIFT); + mtk_disp_pwm_update_bits(mdp, mdp->data->con1, + PWM_PERIOD_MASK | PWM_HIGH_WIDTH_MASK, + value); + + if (mdp->data->has_commit) { + mtk_disp_pwm_update_bits(mdp, mdp->data->commit, + mdp->data->commit_mask, + mdp->data->commit_mask); + mtk_disp_pwm_update_bits(mdp, mdp->data->commit, + mdp->data->commit_mask, + 0x0); + } + + mtk_disp_pwm_update_bits(mdp, DISP_PWM_EN, mdp->data->enable_mask, + mdp->data->enable_mask); + mdp->enabled = true; + + return 0; +} + +static int mtk_disp_pwm_get_state(struct pwm_chip *chip, + struct pwm_device *pwm, + struct pwm_state *state) +{ + struct mtk_disp_pwm *mdp = to_mtk_disp_pwm(chip); + u64 rate, period, high_width; + u32 clk_div, pwm_en, con0, con1; + int err; + + err = clk_prepare_enable(mdp->clk_main); + if (err < 0) { + dev_err(chip->dev, "Can't enable mdp->clk_main: %pe\n", ERR_PTR(err)); + return 0; + } + + err = clk_prepare_enable(mdp->clk_mm); + if (err < 0) { + dev_err(chip->dev, "Can't enable mdp->clk_mm: %pe\n", ERR_PTR(err)); + clk_disable_unprepare(mdp->clk_main); + return 0; + } + + /* + * Apply DISP_PWM_DEBUG settings to choose whether to enable or disable + * registers double buffer and manual commit to working register before + * performing any read/write operation + */ + if (mdp->data->bls_debug) + mtk_disp_pwm_update_bits(mdp, mdp->data->bls_debug, + mdp->data->bls_debug_mask, + mdp->data->bls_debug_mask); + + rate = clk_get_rate(mdp->clk_main); + con0 = readl(mdp->base + mdp->data->con0); + con1 = readl(mdp->base + mdp->data->con1); + pwm_en = readl(mdp->base + DISP_PWM_EN); + state->enabled = !!(pwm_en & mdp->data->enable_mask); + clk_div = FIELD_GET(PWM_CLKDIV_MASK, con0); + period = FIELD_GET(PWM_PERIOD_MASK, con1); + /* + * period has 12 bits, clk_div 11 and NSEC_PER_SEC has 30, + * so period * (clk_div + 1) * NSEC_PER_SEC doesn't overflow. + */ + state->period = DIV64_U64_ROUND_UP(period * (clk_div + 1) * NSEC_PER_SEC, rate); + high_width = FIELD_GET(PWM_HIGH_WIDTH_MASK, con1); + state->duty_cycle = DIV64_U64_ROUND_UP(high_width * (clk_div + 1) * NSEC_PER_SEC, + rate); + state->polarity = PWM_POLARITY_NORMAL; + clk_disable_unprepare(mdp->clk_mm); + clk_disable_unprepare(mdp->clk_main); + + return 0; +} + +static const struct pwm_ops mtk_disp_pwm_ops = { + .apply = mtk_disp_pwm_apply, + .get_state = mtk_disp_pwm_get_state, + .owner = THIS_MODULE, +}; + +static int mtk_disp_pwm_probe(struct platform_device *pdev) +{ + struct mtk_disp_pwm *mdp; + int ret; + + mdp = devm_kzalloc(&pdev->dev, sizeof(*mdp), GFP_KERNEL); + if (!mdp) + return -ENOMEM; + + mdp->data = of_device_get_match_data(&pdev->dev); + + mdp->base = devm_platform_ioremap_resource(pdev, 0); + if (IS_ERR(mdp->base)) + return PTR_ERR(mdp->base); + + mdp->clk_main = devm_clk_get(&pdev->dev, "main"); + if (IS_ERR(mdp->clk_main)) + return PTR_ERR(mdp->clk_main); + + mdp->clk_mm = devm_clk_get(&pdev->dev, "mm"); + if (IS_ERR(mdp->clk_mm)) + return PTR_ERR(mdp->clk_mm); + + mdp->chip.dev = &pdev->dev; + mdp->chip.ops = &mtk_disp_pwm_ops; + mdp->chip.npwm = 1; + + ret = pwmchip_add(&mdp->chip); + if (ret < 0) { + dev_err(&pdev->dev, "pwmchip_add() failed: %pe\n", ERR_PTR(ret)); + return ret; + } + + platform_set_drvdata(pdev, mdp); + + return 0; +} + +static int mtk_disp_pwm_remove(struct platform_device *pdev) +{ + struct mtk_disp_pwm *mdp = platform_get_drvdata(pdev); + + pwmchip_remove(&mdp->chip); + + return 0; +} + +static const struct mtk_pwm_data mt2701_pwm_data = { + .enable_mask = BIT(16), + .con0 = 0xa8, + .con0_sel = 0x2, + .con1 = 0xac, + .has_commit = false, + .bls_debug = 0xb0, + .bls_debug_mask = 0x3, +}; + +static const struct mtk_pwm_data mt8173_pwm_data = { + .enable_mask = BIT(0), + .con0 = 0x10, + .con0_sel = 0x0, + .con1 = 0x14, + .has_commit = true, + .commit = 0x8, + .commit_mask = 0x1, +}; + +static const struct mtk_pwm_data mt8183_pwm_data = { + .enable_mask = BIT(0), + .con0 = 0x18, + .con0_sel = 0x0, + .con1 = 0x1c, + .has_commit = false, + .bls_debug = 0x80, + .bls_debug_mask = 0x3, +}; + +static const struct of_device_id mtk_disp_pwm_of_match[] = { + { .compatible = "mediatek,mt2701-disp-pwm", .data = &mt2701_pwm_data}, + { .compatible = "mediatek,mt6595-disp-pwm", .data = &mt8173_pwm_data}, + { .compatible = "mediatek,mt8173-disp-pwm", .data = &mt8173_pwm_data}, + { .compatible = "mediatek,mt8183-disp-pwm", .data = &mt8183_pwm_data}, + { } +}; +MODULE_DEVICE_TABLE(of, mtk_disp_pwm_of_match); + +static struct platform_driver mtk_disp_pwm_driver = { + .driver = { + .name = "mediatek-disp-pwm", + .of_match_table = mtk_disp_pwm_of_match, + }, + .probe = mtk_disp_pwm_probe, + .remove = mtk_disp_pwm_remove, +}; +module_platform_driver(mtk_disp_pwm_driver); + +MODULE_AUTHOR("YH Huang <yh.huang@mediatek.com>"); +MODULE_DESCRIPTION("MediaTek SoC display PWM driver"); +MODULE_LICENSE("GPL v2"); |