From: Russell King <rmk+kernel@arm.linux.org.uk> To: alsa-devel@alsa-project.org, dri-devel@lists.freedesktop.org, linux-arm-kernel@lists.infradead.org Cc: Fabio Estevam <fabio.estevam@freescale.com>, David Airlie <airlied@linux.ie>, Jaroslav Kysela <perex@perex.cz>, Takashi Iwai <tiwai@suse.de>, Mark Brown <broonie@kernel.org>, Philipp Zabel <p.zabel@pengutronix.de>, Yakir Yang <ykk@rock-chips.com> Subject: [PATCH 08/13] drm: bridge/dw_hdmi: introduce interfaces to enable and disable audio Date: Sat, 09 May 2015 11:26:32 +0100 [thread overview] Message-ID: <E1Yr1xo-0006l0-8E@rmk-PC.arm.linux.org.uk> (raw) In-Reply-To: <20150509102501.GO2067@n2100.arm.linux.org.uk> iMX6 devices suffer from an errata (ERR005174) where the audio FIFO can be emptied while it is partially full, resulting in misalignment of the audio samples. To prevent this, the errata workaround recommends writing N as zero until the audio FIFO has been loaded by DMA. Writing N=0 prevents the HDMI bridge from reading from the audio FIFO, effectively disabling audio. This means we need to provide the audio driver with a pair of functions to enable/disable audio. These are dw_hdmi_audio_enable() and dw_hdmi_audio_disable(). A spinlock is introduced to ensure that setting the CTS/N values can't race, ensuring that the audio driver calling the enable/disable functions (which are called in an atomic context) can't race with a modeset. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> --- drivers/gpu/drm/bridge/dw_hdmi.c | 34 +++++++++++++++++++++++++++++++++- include/drm/bridge/dw_hdmi.h | 2 ++ 2 files changed, 35 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/bridge/dw_hdmi.c b/drivers/gpu/drm/bridge/dw_hdmi.c index 0369fab5c695..adda3a988f36 100644 --- a/drivers/gpu/drm/bridge/dw_hdmi.c +++ b/drivers/gpu/drm/bridge/dw_hdmi.c @@ -18,6 +18,7 @@ #include <linux/hdmi.h> #include <linux/mutex.h> #include <linux/of_device.h> +#include <linux/spinlock.h> #include <drm/drm_of.h> #include <drm/drmP.h> @@ -124,8 +125,12 @@ struct dw_hdmi { struct i2c_adapter *ddc; void __iomem *regs; + spinlock_t audio_lock; struct mutex audio_mutex; unsigned int sample_rate; + unsigned int audio_cts; + unsigned int audio_n; + bool audio_enable; int ratio; void (*write)(struct dw_hdmi *hdmi, u8 val, int offset); @@ -347,7 +352,11 @@ static void hdmi_set_clk_regenerator(struct dw_hdmi *hdmi, dev_dbg(hdmi->dev, "%s: samplerate=%ukHz ratio=%d pixelclk=%luMHz N=%d cts=%d\n", __func__, sample_rate, ratio, pixel_clk, n, cts); - hdmi_set_cts_n(hdmi, cts, n); + spin_lock_irq(&hdmi->audio_lock); + hdmi->audio_n = n; + hdmi->audio_cts = cts; + hdmi_set_cts_n(hdmi, cts, hdmi->audio_enable ? n : 0); + spin_unlock_irq(&hdmi->audio_lock); } static void hdmi_init_clk_regenerator(struct dw_hdmi *hdmi) @@ -376,6 +385,28 @@ void dw_hdmi_set_sample_rate(struct dw_hdmi *hdmi, unsigned int rate) } EXPORT_SYMBOL_GPL(dw_hdmi_set_sample_rate); +void dw_hdmi_audio_enable(struct dw_hdmi *hdmi) +{ + unsigned long flags; + + spin_lock_irqsave(&hdmi->audio_lock, flags); + hdmi->audio_enable = true; + hdmi_set_cts_n(hdmi, hdmi->audio_cts, hdmi->audio_n); + spin_unlock_irqrestore(&hdmi->audio_lock, flags); +} +EXPORT_SYMBOL_GPL(dw_hdmi_audio_enable); + +void dw_hdmi_audio_disable(struct dw_hdmi *hdmi) +{ + unsigned long flags; + + spin_lock_irqsave(&hdmi->audio_lock, flags); + hdmi->audio_enable = false; + hdmi_set_cts_n(hdmi, hdmi->audio_cts, 0); + spin_unlock_irqrestore(&hdmi->audio_lock, flags); +} +EXPORT_SYMBOL_GPL(dw_hdmi_audio_disable); + /* * this submodule is responsible for the video data synchronization. * for example, for RGB 4:4:4 input, the data map is defined as @@ -1578,6 +1609,7 @@ int dw_hdmi_bind(struct device *dev, struct device *master, hdmi->encoder = encoder; mutex_init(&hdmi->audio_mutex); + spin_lock_init(&hdmi->audio_lock); of_property_read_u32(np, "reg-io-width", &val); diff --git a/include/drm/bridge/dw_hdmi.h b/include/drm/bridge/dw_hdmi.h index 763af51e1d60..bae79f3c4d28 100644 --- a/include/drm/bridge/dw_hdmi.h +++ b/include/drm/bridge/dw_hdmi.h @@ -63,5 +63,7 @@ int dw_hdmi_bind(struct device *dev, struct device *master, const struct dw_hdmi_plat_data *plat_data); void dw_hdmi_set_sample_rate(struct dw_hdmi *hdmi, unsigned int rate); +void dw_hdmi_audio_enable(struct dw_hdmi *hdmi); +void dw_hdmi_audio_disable(struct dw_hdmi *hdmi); #endif /* __IMX_HDMI_H__ */ -- 1.8.3.1
WARNING: multiple messages have this Message-ID (diff)
From: rmk+kernel@arm.linux.org.uk (Russell King) To: linux-arm-kernel@lists.infradead.org Subject: [PATCH 08/13] drm: bridge/dw_hdmi: introduce interfaces to enable and disable audio Date: Sat, 09 May 2015 11:26:32 +0100 [thread overview] Message-ID: <E1Yr1xo-0006l0-8E@rmk-PC.arm.linux.org.uk> (raw) In-Reply-To: <20150509102501.GO2067@n2100.arm.linux.org.uk> iMX6 devices suffer from an errata (ERR005174) where the audio FIFO can be emptied while it is partially full, resulting in misalignment of the audio samples. To prevent this, the errata workaround recommends writing N as zero until the audio FIFO has been loaded by DMA. Writing N=0 prevents the HDMI bridge from reading from the audio FIFO, effectively disabling audio. This means we need to provide the audio driver with a pair of functions to enable/disable audio. These are dw_hdmi_audio_enable() and dw_hdmi_audio_disable(). A spinlock is introduced to ensure that setting the CTS/N values can't race, ensuring that the audio driver calling the enable/disable functions (which are called in an atomic context) can't race with a modeset. Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk> --- drivers/gpu/drm/bridge/dw_hdmi.c | 34 +++++++++++++++++++++++++++++++++- include/drm/bridge/dw_hdmi.h | 2 ++ 2 files changed, 35 insertions(+), 1 deletion(-) diff --git a/drivers/gpu/drm/bridge/dw_hdmi.c b/drivers/gpu/drm/bridge/dw_hdmi.c index 0369fab5c695..adda3a988f36 100644 --- a/drivers/gpu/drm/bridge/dw_hdmi.c +++ b/drivers/gpu/drm/bridge/dw_hdmi.c @@ -18,6 +18,7 @@ #include <linux/hdmi.h> #include <linux/mutex.h> #include <linux/of_device.h> +#include <linux/spinlock.h> #include <drm/drm_of.h> #include <drm/drmP.h> @@ -124,8 +125,12 @@ struct dw_hdmi { struct i2c_adapter *ddc; void __iomem *regs; + spinlock_t audio_lock; struct mutex audio_mutex; unsigned int sample_rate; + unsigned int audio_cts; + unsigned int audio_n; + bool audio_enable; int ratio; void (*write)(struct dw_hdmi *hdmi, u8 val, int offset); @@ -347,7 +352,11 @@ static void hdmi_set_clk_regenerator(struct dw_hdmi *hdmi, dev_dbg(hdmi->dev, "%s: samplerate=%ukHz ratio=%d pixelclk=%luMHz N=%d cts=%d\n", __func__, sample_rate, ratio, pixel_clk, n, cts); - hdmi_set_cts_n(hdmi, cts, n); + spin_lock_irq(&hdmi->audio_lock); + hdmi->audio_n = n; + hdmi->audio_cts = cts; + hdmi_set_cts_n(hdmi, cts, hdmi->audio_enable ? n : 0); + spin_unlock_irq(&hdmi->audio_lock); } static void hdmi_init_clk_regenerator(struct dw_hdmi *hdmi) @@ -376,6 +385,28 @@ void dw_hdmi_set_sample_rate(struct dw_hdmi *hdmi, unsigned int rate) } EXPORT_SYMBOL_GPL(dw_hdmi_set_sample_rate); +void dw_hdmi_audio_enable(struct dw_hdmi *hdmi) +{ + unsigned long flags; + + spin_lock_irqsave(&hdmi->audio_lock, flags); + hdmi->audio_enable = true; + hdmi_set_cts_n(hdmi, hdmi->audio_cts, hdmi->audio_n); + spin_unlock_irqrestore(&hdmi->audio_lock, flags); +} +EXPORT_SYMBOL_GPL(dw_hdmi_audio_enable); + +void dw_hdmi_audio_disable(struct dw_hdmi *hdmi) +{ + unsigned long flags; + + spin_lock_irqsave(&hdmi->audio_lock, flags); + hdmi->audio_enable = false; + hdmi_set_cts_n(hdmi, hdmi->audio_cts, 0); + spin_unlock_irqrestore(&hdmi->audio_lock, flags); +} +EXPORT_SYMBOL_GPL(dw_hdmi_audio_disable); + /* * this submodule is responsible for the video data synchronization. * for example, for RGB 4:4:4 input, the data map is defined as @@ -1578,6 +1609,7 @@ int dw_hdmi_bind(struct device *dev, struct device *master, hdmi->encoder = encoder; mutex_init(&hdmi->audio_mutex); + spin_lock_init(&hdmi->audio_lock); of_property_read_u32(np, "reg-io-width", &val); diff --git a/include/drm/bridge/dw_hdmi.h b/include/drm/bridge/dw_hdmi.h index 763af51e1d60..bae79f3c4d28 100644 --- a/include/drm/bridge/dw_hdmi.h +++ b/include/drm/bridge/dw_hdmi.h @@ -63,5 +63,7 @@ int dw_hdmi_bind(struct device *dev, struct device *master, const struct dw_hdmi_plat_data *plat_data); void dw_hdmi_set_sample_rate(struct dw_hdmi *hdmi, unsigned int rate); +void dw_hdmi_audio_enable(struct dw_hdmi *hdmi); +void dw_hdmi_audio_disable(struct dw_hdmi *hdmi); #endif /* __IMX_HDMI_H__ */ -- 1.8.3.1
next prev parent reply other threads:[~2015-05-09 10:26 UTC|newest] Thread overview: 148+ messages / expand[flat|nested] mbox.gz Atom feed top 2015-04-02 9:20 [RFC v2 0/13] dw_hdmi cleanups, audio preparation, helpers and ahb audio support Russell King - ARM Linux 2015-04-02 9:20 ` Russell King - ARM Linux 2015-04-02 9:21 ` [PATCH RFC v2 01/13] drm: imx/dw_hdmi: move phy comments Russell King 2015-04-02 9:21 ` Russell King 2015-04-02 9:21 ` [PATCH RFC v2 02/13] drm: bridge/dw_hdmi: clean up phy configuration Russell King 2015-04-02 9:21 ` Russell King 2015-04-02 9:21 ` [PATCH RFC v2 03/13] drm: bridge/dw_hdmi: clean up hdmi_set_clk_regenerator() Russell King 2015-04-02 9:21 ` Russell King 2015-04-02 9:21 ` [PATCH RFC v2 04/13] drm: bridge/dw_hdmi: use drm_hdmi_avi_infoframe_from_display_mode() Russell King 2015-04-02 9:21 ` Russell King 2015-04-02 9:21 ` [PATCH RFC v2 05/13] drm: bridge/dw_hdmi: simplify hdmi_config_AVI() a little Russell King 2015-04-02 9:21 ` Russell King 2015-04-02 9:21 ` [PATCH RFC v2 06/13] drm: bridge/dw_hdmi: remove mhsyncpolarity/mvsyncpolarity/minterlaced Russell King 2015-04-02 9:21 ` Russell King 2015-04-02 9:21 ` [PATCH RFC v2 07/13] drm: bridge/dw_hdmi: introduce interface to setting sample rate Russell King 2015-04-02 9:21 ` Russell King 2015-04-02 9:21 ` [PATCH RFC v2 08/13] drm: bridge/dw_hdmi: introduce interfaces to enable and disable audio Russell King 2015-04-02 9:21 ` Russell King 2015-04-02 9:22 ` [PATCH RFC v2 09/13] drm/edid: add function to help find SADs Russell King 2015-04-02 9:22 ` Russell King 2015-04-02 9:22 ` [PATCH RFC v2 10/13] sound/core: add DRM ELD helper Russell King 2015-04-02 9:22 ` Russell King 2015-04-05 15:57 ` Takashi Iwai 2015-04-05 15:57 ` Takashi Iwai 2015-04-05 16:20 ` Russell King - ARM Linux 2015-04-05 16:20 ` Russell King - ARM Linux 2015-04-05 16:46 ` Takashi Iwai 2015-04-05 16:46 ` Takashi Iwai 2015-04-05 17:26 ` Russell King - ARM Linux 2015-04-05 17:26 ` Russell King - ARM Linux 2015-05-06 17:02 ` Anssi Hannula 2015-05-06 17:02 ` Anssi Hannula 2015-05-07 10:41 ` Russell King - ARM Linux 2015-05-07 10:41 ` Russell King - ARM Linux 2015-05-07 11:11 ` Lars-Peter Clausen 2015-05-07 11:11 ` [alsa-devel] " Lars-Peter Clausen 2015-05-08 10:56 ` Jyri Sarha 2015-05-08 10:56 ` Jyri Sarha 2015-05-08 11:42 ` Russell King - ARM Linux 2015-05-08 11:42 ` Russell King - ARM Linux 2015-05-05 22:35 ` Mark Brown 2015-05-05 22:35 ` Mark Brown 2015-05-06 8:58 ` Liam Girdwood 2015-05-06 8:58 ` [alsa-devel] " Liam Girdwood 2015-05-08 13:16 ` Jyri Sarha 2015-05-08 13:16 ` Jyri Sarha 2015-05-08 13:27 ` Russell King - ARM Linux 2015-05-08 13:27 ` Russell King - ARM Linux 2015-05-08 13:37 ` Jyri Sarha 2015-05-08 13:37 ` [alsa-devel] " Jyri Sarha 2015-04-02 9:22 ` [PATCH RFC v2 11/13] sound/core: add IEC958 channel status helper Russell King 2015-04-02 9:22 ` Russell King 2015-04-02 9:22 ` [PATCH RFC v2 12/13] drm: bridge/dw_hdmi-ahb-audio: add audio driver Russell King 2015-04-02 9:22 ` Russell King 2015-04-02 9:22 ` [PATCH RFC v2 13/13] drm: bridge/dw_hdmi-ahb-audio: parse ELD from HDMI driver Russell King 2015-04-02 9:22 ` Russell King 2015-05-09 10:25 ` [PATCH v3 0/13] dw_hdmi cleanups, audio preparation, helpers and ahb audio support Russell King - ARM Linux 2015-05-09 10:25 ` Russell King - ARM Linux 2015-05-09 10:25 ` [PATCH 01/13] drm: imx/dw_hdmi: move phy comments Russell King 2015-05-09 10:25 ` Russell King 2015-05-09 10:26 ` [PATCH 02/13] drm: bridge/dw_hdmi: clean up phy configuration Russell King 2015-05-09 10:26 ` Russell King 2015-05-22 15:19 ` Yakir 2015-05-22 15:19 ` Yakir 2015-05-09 10:26 ` [PATCH 03/13] drm: bridge/dw_hdmi: clean up hdmi_set_clk_regenerator() Russell King 2015-05-09 10:26 ` Russell King 2015-05-22 15:22 ` Yakir 2015-05-22 15:22 ` Yakir 2015-05-09 10:26 ` [PATCH 04/13] drm: bridge/dw_hdmi: use drm_hdmi_avi_infoframe_from_display_mode() Russell King 2015-05-09 10:26 ` Russell King 2015-05-09 10:26 ` [PATCH 05/13] drm: bridge/dw_hdmi: simplify hdmi_config_AVI() a little Russell King 2015-05-09 10:26 ` Russell King 2015-05-09 10:26 ` [PATCH 06/13] drm: bridge/dw_hdmi: remove mhsyncpolarity/mvsyncpolarity/minterlaced Russell King 2015-05-09 10:26 ` Russell King 2015-05-09 10:26 ` [PATCH 07/13] drm: bridge/dw_hdmi: introduce interface to setting sample rate Russell King 2015-05-09 10:26 ` Russell King 2015-05-22 15:26 ` Yakir 2015-05-22 15:26 ` Yakir 2015-05-09 10:26 ` Russell King [this message] 2015-05-09 10:26 ` [PATCH 08/13] drm: bridge/dw_hdmi: introduce interfaces to enable and disable audio Russell King 2015-05-22 15:28 ` Yakir 2015-05-22 15:28 ` Yakir 2015-05-09 10:26 ` [PATCH 09/13] drm/edid: add function to help find SADs Russell King 2015-05-09 10:26 ` Russell King 2015-05-09 10:26 ` [PATCH 10/13] sound/core: add DRM ELD helper Russell King 2015-05-09 10:26 ` Russell King 2015-05-22 12:20 ` [alsa-devel] " Mark Brown 2015-05-22 12:20 ` Mark Brown 2015-05-22 13:15 ` Russell King - ARM Linux 2015-05-22 13:15 ` Russell King - ARM Linux 2015-05-22 13:30 ` Takashi Iwai 2015-05-22 13:30 ` Takashi Iwai 2015-05-22 13:53 ` Russell King - ARM Linux 2015-05-22 13:53 ` Russell King - ARM Linux 2015-05-22 13:54 ` Takashi Iwai 2015-05-22 13:54 ` Takashi Iwai 2015-05-22 14:00 ` Russell King - ARM Linux 2015-05-22 14:00 ` Russell King - ARM Linux 2015-05-22 14:02 ` Takashi Iwai 2015-05-22 14:02 ` Takashi Iwai 2015-05-22 14:05 ` Takashi Iwai 2015-05-22 14:05 ` Takashi Iwai 2015-05-22 16:12 ` Russell King - ARM Linux 2015-05-22 16:12 ` Russell King - ARM Linux 2015-05-09 10:26 ` [PATCH 11/13] sound/core: add IEC958 channel status helper Russell King 2015-05-09 10:26 ` Russell King 2015-05-22 12:40 ` Mark Brown 2015-05-22 12:40 ` Mark Brown 2015-05-09 10:26 ` [PATCH 12/13] drm: bridge/dw_hdmi-ahb-audio: add audio driver Russell King 2015-05-09 10:26 ` Russell King 2015-05-09 16:49 ` [alsa-devel] " Anssi Hannula 2015-05-09 16:49 ` Anssi Hannula 2015-05-09 16:55 ` Russell King - ARM Linux 2015-05-09 16:55 ` Russell King - ARM Linux 2015-05-09 17:07 ` Anssi Hannula 2015-05-09 17:07 ` Anssi Hannula 2015-05-09 17:40 ` Russell King - ARM Linux 2015-05-09 17:40 ` Russell King - ARM Linux 2015-05-09 17:53 ` Russell King - ARM Linux 2015-05-09 17:53 ` Russell King - ARM Linux 2015-05-09 17:55 ` Anssi Hannula 2015-05-09 17:55 ` Anssi Hannula 2015-05-09 18:11 ` Russell King - ARM Linux 2015-05-09 18:11 ` Russell King - ARM Linux 2015-05-10 18:59 ` Anssi Hannula 2015-05-10 18:59 ` Anssi Hannula 2015-05-10 19:33 ` Russell King - ARM Linux 2015-05-10 19:33 ` Russell King - ARM Linux 2015-05-10 20:47 ` Anssi Hannula 2015-05-10 20:47 ` Anssi Hannula 2015-05-11 15:58 ` Mark Brown 2015-05-11 15:58 ` [alsa-devel] " Mark Brown 2015-05-09 10:26 ` [PATCH 13/13] drm: bridge/dw_hdmi-ahb-audio: parse ELD from HDMI driver Russell King 2015-05-09 10:26 ` Russell King 2015-05-27 10:43 ` Daniel Vetter 2015-05-27 10:43 ` Daniel Vetter 2015-05-27 11:43 ` Mark Brown 2015-05-27 11:43 ` Mark Brown 2015-05-27 17:31 ` Russell King - ARM Linux 2015-05-27 17:31 ` Russell King - ARM Linux 2015-05-27 21:29 ` Daniel Vetter 2015-05-27 21:29 ` Daniel Vetter 2015-05-27 21:44 ` Russell King - ARM Linux 2015-05-27 21:44 ` Russell King - ARM Linux 2015-05-28 6:43 ` Daniel Vetter 2015-05-28 6:43 ` Daniel Vetter 2015-05-28 4:56 ` [alsa-devel] " Takashi Iwai 2015-05-28 4:56 ` Takashi Iwai
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