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Groups > linux.kernel > #1510076
| From | Lukasz Majewski <l.majewski@majess.pl> |
|---|---|
| Newsgroups | linux.kernel |
| Subject | [PATCH v2 06/10] pwm: imx: Provide atomic PWM support for i.MX PWMv2 |
| Date | 2016-10-27 08:40 +0200 |
| Message-ID | <swMw2-6AV-23@gated-at.bofh.it> (permalink) |
| References | <swMw2-6AV-11@gated-at.bofh.it> |
| Organization | linux.* mail to news gateway |
This commit provides apply() callback implementation for i.MX's PWMv2.
Suggested-by: Stefan Agner <stefan@agner.ch>
Suggested-by: Boris Brezillon <boris.brezillon@free-electrons.com>
Signed-off-by: Lukasz Majewski <l.majewski@majess.pl>
Reviewed-by: Boris Brezillon <boris.brezillon@free-electrons.com>
---
Changes for v2:
- None
---
drivers/pwm/pwm-imx.c | 76 +++++++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 76 insertions(+)
diff --git a/drivers/pwm/pwm-imx.c b/drivers/pwm/pwm-imx.c
index f7c7534..6b7d2f1 100644
--- a/drivers/pwm/pwm-imx.c
+++ b/drivers/pwm/pwm-imx.c
@@ -174,6 +174,81 @@ static void imx_pwm_wait_fifo_slot(struct pwm_chip *chip,
}
}
+static int imx_pwm_apply_v2(struct pwm_chip *chip, struct pwm_device *pwm,
+ struct pwm_state *state)
+{
+ unsigned long period_cycles, duty_cycles, prescale;
+ struct imx_chip *imx = to_imx_chip(chip);
+ struct pwm_state cstate;
+ unsigned long long c;
+ u32 cr = 0;
+ int ret;
+
+ ret = clk_prepare_enable(imx->clk_ipg);
+ if (ret)
+ return ret;
+
+ pwm_get_state(pwm, &cstate);
+
+ c = clk_get_rate(imx->clk_per);
+ c *= state->period;
+
+ do_div(c, 1000000000);
+ period_cycles = c;
+
+ prescale = period_cycles / 0x10000 + 1;
+
+ period_cycles /= prescale;
+ c = (unsigned long long)period_cycles * state->duty_cycle;
+ do_div(c, state->period);
+ 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;
+
+ /* Enable the clock if the PWM is being enabled. */
+ if (state->enabled && !cstate.enabled) {
+ ret = clk_prepare_enable(imx->clk_per);
+ if (ret)
+ return ret;
+ }
+
+ /*
+ * Wait for a free FIFO slot if the PWM is already enabled, and flush
+ * the FIFO if the PWM was disabled and is about to be enabled.
+ */
+ if (cstate.enabled)
+ imx_pwm_wait_fifo_slot(chip, pwm);
+ else if (state->enabled)
+ imx_pwm_sw_reset(chip);
+
+ 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_CLKSRC_IPG_HIGH;
+
+ if (state->enabled)
+ cr |= MX3_PWMCR_EN;
+
+ writel(cr, imx->mmio_base + MX3_PWMCR);
+
+ /* Disable the clock if the PWM is being disabled. */
+ if (!state->enabled && cstate.enabled)
+ clk_disable_unprepare(imx->clk_per);
+
+ clk_disable_unprepare(imx->clk_ipg);
+
+ return 0;
+}
+
static int imx_pwm_config_v2(struct pwm_chip *chip,
struct pwm_device *pwm, int duty_ns, int period_ns)
{
@@ -297,6 +372,7 @@ static struct pwm_ops imx_pwm_ops_v2 = {
.enable = imx_pwm_enable,
.disable = imx_pwm_disable,
.config = imx_pwm_config,
+ .apply = imx_pwm_apply_v2,
.owner = THIS_MODULE,
};
--
2.1.4
Back to linux.kernel | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread
[PATCH v2 00/10] pwm: imx: Provide atomic operation for IMX PWM driver Lukasz Majewski <l.majewski@majess.pl> - 2016-10-27 08:40 +0200
[PATCH v2 06/10] pwm: imx: Provide atomic PWM support for i.MX PWMv2 Lukasz Majewski <l.majewski@majess.pl> - 2016-10-27 08:40 +0200
[PATCH v2 04/10] pwm: imx: Move PWMv2 software reset code to a separate function Lukasz Majewski <l.majewski@majess.pl> - 2016-10-27 08:40 +0200
Re: [PATCH v2 04/10] pwm: imx: Move PWMv2 software reset code to a separate function Philipp Zabel <p.zabel@pengutronix.de> - 2016-11-03 10:40 +0100
[PATCH v2 02/10] pwm: imx: Add separate set of pwm ops for PWMv1 and PWMv2 Lukasz Majewski <l.majewski@majess.pl> - 2016-10-27 08:40 +0200
[PATCH v2 05/10] pwm: imx: Move PWMv2 wait for fifo slot code to a separate function Lukasz Majewski <l.majewski@majess.pl> - 2016-10-27 08:50 +0200
[PATCH v2 03/10] pwm: imx: Rewrite imx_pwm_*_v1 code to facilitate switch to atomic pwm operation Lukasz Majewski <l.majewski@majess.pl> - 2016-10-27 08:50 +0200
Re: [PATCH v2 03/10] pwm: imx: Rewrite imx_pwm_*_v1 code to facilitate switch to atomic pwm operation Boris Brezillon <boris.brezillon@free-electrons.com> - 2016-10-27 09:50 +0200
Re: [PATCH v2 03/10] pwm: imx: Rewrite imx_pwm_*_v1 code to facilitate switch to atomic pwm operation Lukasz Majewski <l.majewski@majess.pl> - 2016-10-27 16:40 +0200
Re: [PATCH v2 03/10] pwm: imx: Rewrite imx_pwm_*_v1 code to facilitate switch to atomic pwm operation Sascha Hauer <s.hauer@pengutronix.de> - 2016-10-31 07:10 +0100
Re: [PATCH v2 03/10] pwm: imx: Rewrite imx_pwm_*_v1 code to facilitate switch to atomic pwm operation Lukasz Majewski <l.majewski@majess.pl> - 2016-10-31 09:20 +0100
Re: [PATCH v2 03/10] pwm: imx: Rewrite imx_pwm_*_v1 code to facilitate switch to atomic pwm operation Sascha Hauer <s.hauer@pengutronix.de> - 2016-10-31 10:30 +0100
Re: [PATCH v2 03/10] pwm: imx: Rewrite imx_pwm_*_v1 code to facilitate switch to atomic pwm operation Sascha Hauer <s.hauer@pengutronix.de> - 2016-10-31 10:40 +0100
Re: [PATCH v2 03/10] pwm: imx: Rewrite imx_pwm_*_v1 code to facilitate switch to atomic pwm operation Lukasz Majewski <l.majewski@majess.pl> - 2016-10-31 13:00 +0100
Re: [PATCH v2 03/10] pwm: imx: Rewrite imx_pwm_*_v1 code to facilitate switch to atomic pwm operation Lukasz Majewski <l.majewski@majess.pl> - 2016-11-01 07:00 +0100
Re: [PATCH v2 03/10] pwm: imx: Rewrite imx_pwm_*_v1 code to facilitate switch to atomic pwm operation Sascha Hauer <s.hauer@pengutronix.de> - 2016-11-01 08:20 +0100
Re: [PATCH v2 03/10] pwm: imx: Rewrite imx_pwm_*_v1 code to facilitate switch to atomic pwm operation Lukasz Majewski <l.majewski@majess.pl> - 2016-11-01 09:30 +0100
Re: [PATCH v2 03/10] pwm: imx: Rewrite imx_pwm_*_v1 code to facilitate switch to atomic pwm operation Sascha Hauer <s.hauer@pengutronix.de> - 2016-11-01 10:00 +0100
Re: [PATCH v2 03/10] pwm: imx: Rewrite imx_pwm_*_v1 code to facilitate switch to atomic pwm operation Lothar Waßmann <LW@KARO-electronics.de> - 2016-11-02 08:40 +0100
Re: [PATCH v2 03/10] pwm: imx: Rewrite imx_pwm_*_v1 code to facilitate switch to atomic pwm operation Sascha Hauer <s.hauer@pengutronix.de> - 2016-11-02 08:40 +0100
Re: [PATCH v2 03/10] pwm: imx: Rewrite imx_pwm_*_v1 code to facilitate switch to atomic pwm operation Lothar Waßmann <LW@KARO-electronics.de> - 2016-11-02 09:00 +0100
Re: [PATCH v2 03/10] pwm: imx: Rewrite imx_pwm_*_v1 code to facilitate switch to atomic pwm operation Sascha Hauer <s.hauer@pengutronix.de> - 2016-11-02 09:10 +0100
Re: [PATCH v2 03/10] pwm: imx: Rewrite imx_pwm_*_v1 code to facilitate switch to atomic pwm operation Lothar Waßmann <LW@KARO-electronics.de> - 2016-11-02 10:00 +0100
Re: [PATCH v2 03/10] pwm: imx: Rewrite imx_pwm_*_v1 code to facilitate switch to atomic pwm operation Philipp Zabel <p.zabel@pengutronix.de> - 2016-11-02 10:40 +0100
[PATCH v2 08/10] pwm: core: make the PWM_POLARITY flag in DTB optional Lukasz Majewski <l.majewski@majess.pl> - 2016-10-27 08:50 +0200
[PATCH v2 10/10] pwm: imx: Add polarity inversion support to i.MX's PWMv2 Lukasz Majewski <l.majewski@majess.pl> - 2016-10-27 08:50 +0200
[PATCH v2 07/10] pwm: imx: Remove redundant i.MX PWMv2 code Lukasz Majewski <l.majewski@majess.pl> - 2016-10-27 08:50 +0200
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