[PATCH 08/15] pwm: Add new pwm-samsung driver
Tomasz Figa
tomasz.figa at gmail.com
Thu Jun 13 16:18:16 EDT 2013
On Thursday 13 of June 2013 22:14:19 Heiko Stübner wrote:
> Am Mittwoch, 5. Juni 2013, 23:18:13 schrieb Tomasz Figa:
> > This patch introduces new Samsung PWM driver, which uses Samsung
> > PWM/timer master driver to control shared parts of the hardware.
> >
> > Signed-off-by: Tomasz Figa <tomasz.figa at gmail.com>
> > ---
> >
> > drivers/pwm/Makefile | 1 +
> > drivers/pwm/pwm-samsung.c | 528
> >
> > ++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 529
> > insertions(+)
> >
> > create mode 100644 drivers/pwm/pwm-samsung.c
> >
> > diff --git a/drivers/pwm/Makefile b/drivers/pwm/Makefile
>
> [...]
>
> > +static int pwm_samsung_probe(struct platform_device *pdev)
> > +{
> > + struct device *dev = &pdev->dev;
> > + struct samsung_pwm_chip *chip;
> > + struct resource *res;
> > + int ret;
> > +
> > + chip = devm_kzalloc(&pdev->dev, sizeof(*chip), GFP_KERNEL);
> > + if (chip == NULL) {
> > + dev_err(dev, "failed to allocate driver data\n");
> > + return -ENOMEM;
> > + }
> > +
> > + chip->chip.dev = &pdev->dev;
> > + chip->chip.ops = &pwm_samsung_ops;
> > + chip->chip.base = -1;
> > + chip->chip.npwm = SAMSUNG_PWM_NUM;
> > +
> > + if (pdev->dev.of_node) {
> > + ret = pwm_samsung_parse_dt(chip);
> > + if (ret)
> > + return ret;
> > +
> > + chip->chip.of_xlate = of_pwm_xlate_with_flags;
> > + chip->chip.of_pwm_n_cells = 3;
> > + } else {
> > + if (!pdev->dev.platform_data) {
> > + dev_err(&pdev->dev, "no platform data
specified\n");
> > + return -EINVAL;
> > + }
> > +
> > + memcpy(&chip->variant, pdev->dev.platform_data,
> > + sizeof(chip-
>variant));
> > + }
> > +
> > + res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
> > + if (!res) {
> > + dev_err(&pdev->dev, "failed to get mem resource\n");
> > + return -ENOMEM;
> > + }
> > +
> > + chip->base = devm_request_and_ioremap(&pdev->dev, res);
> > + if (!chip->base) {
> > + dev_err(&pdev->dev, "failed to request and map
registers\n");
> > + return -ENOMEM;
> > + }
> > +
> > + chip->base_clk = devm_clk_get(&pdev->dev, "timers");
> > + if (IS_ERR(chip->base_clk)) {
> > + dev_err(dev, "failed to get timer base clk\n");
> > + return PTR_ERR(chip->base_clk);
> > + }
> > + clk_prepare_enable(chip->base_clk);
> > +
> > + chip->tclk0 = devm_clk_get(&pdev->dev, "pwm-tclk0");
> > + chip->tclk1 = devm_clk_get(&pdev->dev, "pwm-tclk1");
> > +
> > + ret = pwmchip_add(&chip->chip);
> > + if (ret < 0) {
> > + dev_err(dev, "failed to register pwm\n");
> > + goto err_clk_disable;
> > + }
> > +
> > + dev_info(dev, "base_clk at %lu, tclk0 at %lu, tclk1 at %lu\n",
> > + clk_get_rate(chip->base_clk),
> > + !IS_ERR(chip->tclk0) ? clk_get_rate(chip->tclk0) : 0,
> > + !IS_ERR(chip->tclk1) ? clk_get_rate(chip->tclk1) : 0);
>
> hmm, these values simply tell some internal state of the pwm, so
> wouldn't a dev_dbg be more appropriate?
Hmm, I have kept it as dev_info as in old driver, but now as you say it,
dev_dbg might be more appropriate indeed, as it isn't really anything
important that users should know...
Best regards,
Tomasz
> > +
> > + platform_set_drvdata(pdev, chip);
> > +
> > + return 0;
> > +
> > +err_clk_disable:
> > + clk_disable_unprepare(chip->base_clk);
> > +
> > + return ret;
> > +}
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