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path: root/drivers/pwm/pwm-clps711x.c
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Diffstat (limited to 'drivers/pwm/pwm-clps711x.c')
-rw-r--r--drivers/pwm/pwm-clps711x.c131
1 files changed, 131 insertions, 0 deletions
diff --git a/drivers/pwm/pwm-clps711x.c b/drivers/pwm/pwm-clps711x.c
new file mode 100644
index 0000000000..b0d91142da
--- /dev/null
+++ b/drivers/pwm/pwm-clps711x.c
@@ -0,0 +1,131 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Cirrus Logic CLPS711X PWM driver
+ * Author: Alexander Shiyan <shc_work@mail.ru>
+ */
+
+#include <linux/clk.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/pwm.h>
+
+struct clps711x_chip {
+ struct pwm_chip chip;
+ void __iomem *pmpcon;
+ struct clk *clk;
+ spinlock_t lock;
+};
+
+static inline struct clps711x_chip *to_clps711x_chip(struct pwm_chip *chip)
+{
+ return container_of(chip, struct clps711x_chip, chip);
+}
+
+static int clps711x_pwm_request(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+ struct clps711x_chip *priv = to_clps711x_chip(chip);
+ unsigned int freq = clk_get_rate(priv->clk);
+
+ if (!freq)
+ return -EINVAL;
+
+ /* Store constant period value */
+ pwm->args.period = DIV_ROUND_CLOSEST(NSEC_PER_SEC, freq);
+
+ return 0;
+}
+
+static int clps711x_pwm_apply(struct pwm_chip *chip, struct pwm_device *pwm,
+ const struct pwm_state *state)
+{
+ struct clps711x_chip *priv = to_clps711x_chip(chip);
+ /* PWM0 - bits 4..7, PWM1 - bits 8..11 */
+ u32 shift = (pwm->hwpwm + 1) * 4;
+ unsigned long flags;
+ u32 pmpcon, val;
+
+ if (state->polarity != PWM_POLARITY_NORMAL)
+ return -EINVAL;
+
+ if (state->period != pwm->args.period)
+ return -EINVAL;
+
+ if (state->enabled)
+ val = mul_u64_u64_div_u64(state->duty_cycle, 0xf, state->period);
+ else
+ val = 0;
+
+ spin_lock_irqsave(&priv->lock, flags);
+
+ pmpcon = readl(priv->pmpcon);
+ pmpcon &= ~(0xf << shift);
+ pmpcon |= val << shift;
+ writel(pmpcon, priv->pmpcon);
+
+ spin_unlock_irqrestore(&priv->lock, flags);
+
+ return 0;
+}
+
+static const struct pwm_ops clps711x_pwm_ops = {
+ .request = clps711x_pwm_request,
+ .apply = clps711x_pwm_apply,
+ .owner = THIS_MODULE,
+};
+
+static struct pwm_device *clps711x_pwm_xlate(struct pwm_chip *chip,
+ const struct of_phandle_args *args)
+{
+ if (args->args[0] >= chip->npwm)
+ return ERR_PTR(-EINVAL);
+
+ return pwm_request_from_chip(chip, args->args[0], NULL);
+}
+
+static int clps711x_pwm_probe(struct platform_device *pdev)
+{
+ struct clps711x_chip *priv;
+
+ priv = devm_kzalloc(&pdev->dev, sizeof(*priv), GFP_KERNEL);
+ if (!priv)
+ return -ENOMEM;
+
+ priv->pmpcon = devm_platform_ioremap_resource(pdev, 0);
+ if (IS_ERR(priv->pmpcon))
+ return PTR_ERR(priv->pmpcon);
+
+ priv->clk = devm_clk_get(&pdev->dev, NULL);
+ if (IS_ERR(priv->clk))
+ return PTR_ERR(priv->clk);
+
+ priv->chip.ops = &clps711x_pwm_ops;
+ priv->chip.dev = &pdev->dev;
+ priv->chip.npwm = 2;
+ priv->chip.of_xlate = clps711x_pwm_xlate;
+ priv->chip.of_pwm_n_cells = 1;
+
+ spin_lock_init(&priv->lock);
+
+ return devm_pwmchip_add(&pdev->dev, &priv->chip);
+}
+
+static const struct of_device_id __maybe_unused clps711x_pwm_dt_ids[] = {
+ { .compatible = "cirrus,ep7209-pwm", },
+ { }
+};
+MODULE_DEVICE_TABLE(of, clps711x_pwm_dt_ids);
+
+static struct platform_driver clps711x_pwm_driver = {
+ .driver = {
+ .name = "clps711x-pwm",
+ .of_match_table = of_match_ptr(clps711x_pwm_dt_ids),
+ },
+ .probe = clps711x_pwm_probe,
+};
+module_platform_driver(clps711x_pwm_driver);
+
+MODULE_AUTHOR("Alexander Shiyan <shc_work@mail.ru>");
+MODULE_DESCRIPTION("Cirrus Logic CLPS711X PWM driver");
+MODULE_LICENSE("GPL");