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author | Russell King <rmk+kernel@arm.linux.org.uk> | 2015-02-02 10:55:38 +0000 |
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committer | Russell King <rmk+kernel@arm.linux.org.uk> | 2015-03-30 19:42:37 +0100 |
commit | 622494a3560b13e05c9f2049bfab8e7fb12c67a2 (patch) | |
tree | 179bdf7557f4defb5b078778da9da7ad59ccdc9d /drivers/gpu/drm/bridge | |
parent | 6bcf495317857e4e4cfb2e6f57fa8230cedc1362 (diff) | |
download | blackbird-op-linux-622494a3560b13e05c9f2049bfab8e7fb12c67a2.tar.gz blackbird-op-linux-622494a3560b13e05c9f2049bfab8e7fb12c67a2.zip |
drm: bridge/dw_hdmi: adjust n/cts setting order
Patch derived from one from Yakir Yang. Yakir Yang says:
For Designerware HDMI, the following write sequence is recommended:
1. aud_n3 (set bit ncts_atomic_write if desired)
2. aud_cts3 (set CTS_manual and CTS value if desired/enabled)
3. aud_cts2 (required in CTS_manual)
4. aud_cts1 (required in CTS_manual)
5. aud_n3 (bit ncts_atomic_write with same value as in step 1.)
6. aud_n2
7. aud_n1
However, avoid the ncts_atomic_write_bit and CTS_manual settings in this
patch, both of which are marked reserved in the iMX6 documentation. All
iMX6 code in the wild seems to want CTS_manual cleared.
Having requested clarification from FSL, it appears that neither of
these bits are implemented in their version of the IP.
Acked-by: Philipp Zabel <p.zabel@pengutronix.de>
Tested-by: Philipp Zabel <p.zabel@pengutronix.de>
Acked-by: Andy Yan <andy.yan@rock-chips.com>
Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>
Diffstat (limited to 'drivers/gpu/drm/bridge')
-rw-r--r-- | drivers/gpu/drm/bridge/dw_hdmi.c | 16 |
1 files changed, 8 insertions, 8 deletions
diff --git a/drivers/gpu/drm/bridge/dw_hdmi.c b/drivers/gpu/drm/bridge/dw_hdmi.c index b75922d4901e..cca1c3d165e2 100644 --- a/drivers/gpu/drm/bridge/dw_hdmi.c +++ b/drivers/gpu/drm/bridge/dw_hdmi.c @@ -182,20 +182,20 @@ static void hdmi_mask_writeb(struct dw_hdmi *hdmi, u8 data, unsigned int reg, static void hdmi_set_cts_n(struct dw_hdmi *hdmi, unsigned int cts, unsigned int n) { - hdmi_writeb(hdmi, n & 0xff, HDMI_AUD_N1); - hdmi_writeb(hdmi, (n >> 8) & 0xff, HDMI_AUD_N2); - hdmi_writeb(hdmi, (n >> 16) & 0x0f, HDMI_AUD_N3); + /* Must be set/cleared first */ + hdmi_modb(hdmi, 0, HDMI_AUD_CTS3_CTS_MANUAL, HDMI_AUD_CTS3); /* nshift factor = 0 */ hdmi_modb(hdmi, 0, HDMI_AUD_CTS3_N_SHIFT_MASK, HDMI_AUD_CTS3); - /* Must be set/cleared first */ - hdmi_modb(hdmi, 0, HDMI_AUD_CTS3_CTS_MANUAL, HDMI_AUD_CTS3); - - hdmi_writeb(hdmi, cts & 0xff, HDMI_AUD_CTS1); - hdmi_writeb(hdmi, (cts >> 8) & 0xff, HDMI_AUD_CTS2); hdmi_writeb(hdmi, ((cts >> 16) & HDMI_AUD_CTS3_AUDCTS19_16_MASK) | HDMI_AUD_CTS3_CTS_MANUAL, HDMI_AUD_CTS3); + hdmi_writeb(hdmi, (cts >> 8) & 0xff, HDMI_AUD_CTS2); + hdmi_writeb(hdmi, cts & 0xff, HDMI_AUD_CTS1); + + hdmi_writeb(hdmi, (n >> 16) & 0x0f, HDMI_AUD_N3); + hdmi_writeb(hdmi, (n >> 8) & 0xff, HDMI_AUD_N2); + hdmi_writeb(hdmi, n & 0xff, HDMI_AUD_N1); } static unsigned int hdmi_compute_n(unsigned int freq, unsigned long pixel_clk, |