Add OPP and SoC core voltage scaling support to the HDMI driver. This is required for enabling system-wide DVFS on older Tegra SoCs. Signed-off-by: Dmitry Osipenko <digetx@xxxxxxxxx> --- drivers/gpu/drm/tegra/hdmi.c | 63 +++++++++++++++++++++++++++++++++++- 1 file changed, 62 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/tegra/hdmi.c b/drivers/gpu/drm/tegra/hdmi.c index d09a24931c87..92e96990854b 100644 --- a/drivers/gpu/drm/tegra/hdmi.c +++ b/drivers/gpu/drm/tegra/hdmi.c @@ -11,6 +11,7 @@ #include <linux/math64.h> #include <linux/module.h> #include <linux/of_device.h> +#include <linux/pm_opp.h> #include <linux/pm_runtime.h> #include <linux/regulator/consumer.h> #include <linux/reset.h> @@ -1195,7 +1196,7 @@ static void tegra_hdmi_encoder_enable(struct drm_encoder *encoder) h_back_porch = mode->htotal - mode->hsync_end; h_front_porch = mode->hsync_start - mode->hdisplay; - err = clk_set_rate(hdmi->clk, hdmi->pixel_clock); + err = dev_pm_opp_set_rate(hdmi->dev, hdmi->pixel_clock); if (err < 0) { dev_err(hdmi->dev, "failed to set HDMI clock frequency: %d\n", err); @@ -1499,6 +1500,7 @@ static int tegra_hdmi_runtime_suspend(struct host1x_client *client) usleep_range(1000, 2000); clk_disable_unprepare(hdmi->clk); + dev_pm_opp_set_rate(hdmi->dev, 0); pm_runtime_put_sync(dev); return 0; @@ -1633,6 +1635,60 @@ static irqreturn_t tegra_hdmi_irq(int irq, void *data) return IRQ_HANDLED; } +static void tegra_hdmi_deinit_opp_table(void *data) +{ + struct device *dev = data; + struct opp_table *opp_table; + + opp_table = dev_pm_opp_get_opp_table(dev); + dev_pm_opp_of_remove_table(dev); + dev_pm_opp_put_regulators(opp_table); + dev_pm_opp_put_opp_table(opp_table); +} + +static int devm_tegra_hdmi_init_opp_table(struct device *dev) +{ + struct opp_table *opp_table; + const char *rname = "core"; + int err; + + /* voltage scaling is optional */ + if (device_property_present(dev, "core-supply")) + opp_table = dev_pm_opp_set_regulators(dev, &rname, 1); + else + opp_table = dev_pm_opp_get_opp_table(dev); + + if (IS_ERR(opp_table)) + return dev_err_probe(dev, PTR_ERR(opp_table), + "failed to prepare OPP table\n"); + + /* + * OPP table presence is optional and we want the set_rate() of OPP + * API to work similarly to clk_set_rate() if table is missing in a + * device-tree. The add_table() errors out if OPP is missing in DT. + */ + if (device_property_present(dev, "operating-points-v2")) { + err = dev_pm_opp_of_add_table(dev); + if (err) { + dev_err(dev, "failed to add OPP table: %d\n", err); + goto put_table; + } + } + + err = devm_add_action(dev, tegra_hdmi_deinit_opp_table, dev); + if (err) + goto remove_table; + + return 0; + +remove_table: + dev_pm_opp_of_remove_table(dev); +put_table: + dev_pm_opp_put_regulators(opp_table); + + return err; +} + static int tegra_hdmi_probe(struct platform_device *pdev) { const char *level = KERN_ERR; @@ -1667,6 +1723,11 @@ static int tegra_hdmi_probe(struct platform_device *pdev) if (IS_ERR(hdmi->clk_parent)) return PTR_ERR(hdmi->clk_parent); + err = devm_tegra_hdmi_init_opp_table(&pdev->dev); + if (err) + return dev_err_probe(&pdev->dev, err, + "failed to initialize OPP\n"); + err = clk_set_parent(hdmi->clk, hdmi->clk_parent); if (err < 0) { dev_err(&pdev->dev, "failed to setup clocks: %d\n", err); -- 2.27.0 _______________________________________________ devel mailing list devel@xxxxxxxxxxxxxxxxxxxxxx http://driverdev.linuxdriverproject.org/mailman/listinfo/driverdev-devel