Merge branch 'for-3.6' of git://gitorious.org/linux-pwm/linux-pwm

Pull PWM subsystem from Thierry Reding:
 "The new PWM subsystem aims at collecting all implementations of the
  legacy PWM API and to eventually replace it completely.

  The subsystem has been in development for over half a year now and
  many drivers have already been converted.  It has been in linux-next
  for a couple of weeks and there have been no major issues so I think
  it is ready for inclusion in your tree."

Arnd Bergmann <arnd@arndb.de>:
 "Very much Ack on the new subsystem.  It uses the interface
  declarations as the previously separate pwm drivers, so nothing
  changes for now in the drivers using it, although it enables us to
  change those more easily in the future if we want to.

  This work is also one of the missing pieces that are required to
  eventually build ARM kernels for multiple platforms, which is
  currently prohibited (amongs other things) by the fact that you cannot
  have more than one driver exporting the pwm functions."

Tested-and-acked-by: Alexandre Courbot <acourbot@nvidia.com>
Acked-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Philip, Avinash <avinashphilip@ti.com> # TI's AM33xx platforms
Acked-By: Alexandre Pereira da Silva <aletes.xgr@gmail.com> # LPC32XX
Acked-by: Arnd Bergmann <arnd@arndb.de>
Acked-by: Sachin Kamat <sachin.kamat@linaro.org>

Fix up trivial conflicts with other cleanups and DT updates.

* 'for-3.6' of git://gitorious.org/linux-pwm/linux-pwm: (36 commits)
  pwm: pwm-tiehrpwm: PWM driver support for EHRPWM
  pwm: pwm-tiecap: PWM driver support for ECAP APWM
  pwm: fix used-uninitialized warning in pwm_get()
  pwm: add lpc32xx PWM support
  pwm_backlight: pass correct brightness to callback
  pwm: Use pr_* functions in pwm-samsung.c file
  pwm: Convert pwm-samsung to use devm_* APIs
  pwm: Convert pwm-tegra to use devm_clk_get()
  pwm: pwm-mxs: Return proper error if pwmchip_remove() fails
  pwm: pwm-bfin: Return proper error if pwmchip_remove() fails
  pwm: pxa: Propagate pwmchip_remove() error
  pwm: Convert pwm-pxa to use devm_* APIs
  pwm: Convert pwm-vt8500 to use devm_* APIs
  pwm: Convert pwm-imx to use devm_* APIs
  pwm: Conflict with legacy PWM API
  pwm: pwm-mxs: add pinctrl support
  pwm: pwm-mxs: use devm_* managed functions
  pwm: pwm-mxs: use global reset function stmp_reset_block
  pwm: pwm-mxs: encode soc name in compatible string
  pwm: Take over maintainership of the PWM subsystem
  ...

1 files changed, 230 insertions, 0 deletions

diff --git a/drivers/pwm/pwm-imx.c b/drivers/pwm/pwm-imx.c
new file mode 100644
index 000000000000..2a0b35333972
--- /dev/null
+++ b/drivers/pwm/pwm-imx.c
@@ -0,0 +1,230 @@
+/*
+ * simple driver for PWM (Pulse Width Modulator) controller
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ *
+ * Derived from pxa PWM driver by eric miao <eric.miao@marvell.com>
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/err.h>
+#include <linux/clk.h>
+#include <linux/io.h>
+#include <linux/pwm.h>
+#include <mach/hardware.h>
+
+
+/* i.MX1 and i.MX21 share the same PWM function block: */
+
+#define MX1_PWMC    0x00   /* PWM Control Register */
+#define MX1_PWMS    0x04   /* PWM Sample Register */
+#define MX1_PWMP    0x08   /* PWM Period Register */
+
+
+/* i.MX27, i.MX31, i.MX35 share the same PWM function block: */
+
+#define MX3_PWMCR                 0x00    /* PWM Control Register */
+#define MX3_PWMSAR                0x0C    /* PWM Sample Register */
+#define MX3_PWMPR                 0x10    /* PWM Period Register */
+#define MX3_PWMCR_PRESCALER(x)    (((x - 1) & 0xFFF) << 4)
+#define MX3_PWMCR_DOZEEN                (1 << 24)
+#define MX3_PWMCR_WAITEN                (1 << 23)
+#define MX3_PWMCR_DBGEN			(1 << 22)
+#define MX3_PWMCR_CLKSRC_IPG_HIGH (2 << 16)
+#define MX3_PWMCR_CLKSRC_IPG      (1 << 16)
+#define MX3_PWMCR_EN              (1 << 0)
+
+struct imx_chip {
+	struct clk	*clk;
+
+	int		clk_enabled;
+	void __iomem	*mmio_base;
+
+	struct pwm_chip	chip;
+};
+
+#define to_imx_chip(chip)	container_of(chip, struct imx_chip, chip)
+
+static int imx_pwm_config(struct pwm_chip *chip,
+		struct pwm_device *pwm, int duty_ns, int period_ns)
+{
+	struct imx_chip *imx = to_imx_chip(chip);
+
+	if (!(cpu_is_mx1() || cpu_is_mx21())) {
+		unsigned long long c;
+		unsigned long period_cycles, duty_cycles, prescale;
+		u32 cr;
+
+		c = clk_get_rate(imx->clk);
+		c = c * period_ns;
+		do_div(c, 1000000000);
+		period_cycles = c;
+
+		prescale = period_cycles / 0x10000 + 1;
+
+		period_cycles /= prescale;
+		c = (unsigned long long)period_cycles * duty_ns;
+		do_div(c, period_ns);
+		duty_cycles = c;
+
+		/*
+		 * according to imx pwm RM, the real period value should be
+		 * PERIOD value in PWMPR plus 2.
+		 */
+		if (period_cycles > 2)
+			period_cycles -= 2;
+		else
+			period_cycles = 0;
+
+		writel(duty_cycles, imx->mmio_base + MX3_PWMSAR);
+		writel(period_cycles, imx->mmio_base + MX3_PWMPR);
+
+		cr = MX3_PWMCR_PRESCALER(prescale) |
+			MX3_PWMCR_DOZEEN | MX3_PWMCR_WAITEN |
+			MX3_PWMCR_DBGEN | MX3_PWMCR_EN;
+
+		if (cpu_is_mx25())
+			cr |= MX3_PWMCR_CLKSRC_IPG;
+		else
+			cr |= MX3_PWMCR_CLKSRC_IPG_HIGH;
+
+		writel(cr, imx->mmio_base + MX3_PWMCR);
+	} else if (cpu_is_mx1() || cpu_is_mx21()) {
+		/* The PWM subsystem allows for exact frequencies. However,
+		 * I cannot connect a scope on my device to the PWM line and
+		 * thus cannot provide the program the PWM controller
+		 * exactly. Instead, I'm relying on the fact that the
+		 * Bootloader (u-boot or WinCE+haret) has programmed the PWM
+		 * function group already. So I'll just modify the PWM sample
+		 * register to follow the ratio of duty_ns vs. period_ns
+		 * accordingly.
+		 *
+		 * This is good enough for programming the brightness of
+		 * the LCD backlight.
+		 *
+		 * The real implementation would divide PERCLK[0] first by
+		 * both the prescaler (/1 .. /128) and then by CLKSEL
+		 * (/2 .. /16).
+		 */
+		u32 max = readl(imx->mmio_base + MX1_PWMP);
+		u32 p = max * duty_ns / period_ns;
+		writel(max - p, imx->mmio_base + MX1_PWMS);
+	} else {
+		BUG();
+	}
+
+	return 0;
+}
+
+static int imx_pwm_enable(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+	struct imx_chip *imx = to_imx_chip(chip);
+	int rc = 0;
+
+	if (!imx->clk_enabled) {
+		rc = clk_prepare_enable(imx->clk);
+		if (!rc)
+			imx->clk_enabled = 1;
+	}
+	return rc;
+}
+
+static void imx_pwm_disable(struct pwm_chip *chip, struct pwm_device *pwm)
+{
+	struct imx_chip *imx = to_imx_chip(chip);
+
+	writel(0, imx->mmio_base + MX3_PWMCR);
+
+	if (imx->clk_enabled) {
+		clk_disable_unprepare(imx->clk);
+		imx->clk_enabled = 0;
+	}
+}
+
+static struct pwm_ops imx_pwm_ops = {
+	.enable = imx_pwm_enable,
+	.disable = imx_pwm_disable,
+	.config = imx_pwm_config,
+	.owner = THIS_MODULE,
+};
+
+static int __devinit imx_pwm_probe(struct platform_device *pdev)
+{
+	struct imx_chip *imx;
+	struct resource *r;
+	int ret = 0;
+
+	imx = devm_kzalloc(&pdev->dev, sizeof(*imx), GFP_KERNEL);
+	if (imx == NULL) {
+		dev_err(&pdev->dev, "failed to allocate memory\n");
+		return -ENOMEM;
+	}
+
+	imx->clk = devm_clk_get(&pdev->dev, "pwm");
+
+	if (IS_ERR(imx->clk))
+		return PTR_ERR(imx->clk);
+
+	imx->chip.ops = &imx_pwm_ops;
+	imx->chip.dev = &pdev->dev;
+	imx->chip.base = -1;
+	imx->chip.npwm = 1;
+
+	imx->clk_enabled = 0;
+
+	r = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+	if (r == NULL) {
+		dev_err(&pdev->dev, "no memory resource defined\n");
+		return -ENODEV;
+	}
+
+	imx->mmio_base = devm_request_and_ioremap(&pdev->dev, r);
+	if (imx->mmio_base == NULL)
+		return -EADDRNOTAVAIL;
+
+	ret = pwmchip_add(&imx->chip);
+	if (ret < 0)
+		return ret;
+
+	platform_set_drvdata(pdev, imx);
+	return 0;
+}
+
+static int __devexit imx_pwm_remove(struct platform_device *pdev)
+{
+	struct imx_chip *imx;
+
+	imx = platform_get_drvdata(pdev);
+	if (imx == NULL)
+		return -ENODEV;
+
+	return pwmchip_remove(&imx->chip);
+}
+
+static struct platform_driver imx_pwm_driver = {
+	.driver		= {
+		.name	= "mxc_pwm",
+	},
+	.probe		= imx_pwm_probe,
+	.remove		= __devexit_p(imx_pwm_remove),
+};
+
+static int __init imx_pwm_init(void)
+{
+	return platform_driver_register(&imx_pwm_driver);
+}
+arch_initcall(imx_pwm_init);
+
+static void __exit imx_pwm_exit(void)
+{
+	platform_driver_unregister(&imx_pwm_driver);
+}
+module_exit(imx_pwm_exit);
+
+MODULE_LICENSE("GPL v2");
+MODULE_AUTHOR("Sascha Hauer <s.hauer@pengutronix.de>");