From c4e4fccc5d52d881afaac11d3353265ef4eccb8b Mon Sep 17 00:00:00 2001 From: Wayne Lin Date: Fri, 3 Jan 2020 13:50:01 +0800 Subject: drm/dp_mst: correct the shifting in DP_REMOTE_I2C_READ [Why] According to DP spec, it should shift left 4 digits for NO_STOP_BIT in REMOTE_I2C_READ message. Not 5 digits. In current code, NO_STOP_BIT is always set to zero which means I2C master is always generating a I2C stop at the end of each I2C write transaction while handling REMOTE_I2C_READ sideband message. This issue might have the generated I2C signal not meeting the requirement. Take random read in I2C for instance, I2C master should generate a repeat start to start to read data after writing the read address. This issue will cause the I2C master to generate a stop-start rather than a re-start which is not expected in I2C random read. [How] Correct the shifting value of NO_STOP_BIT for DP_REMOTE_I2C_READ case in drm_dp_encode_sideband_req(). Changes since v1:(https://patchwork.kernel.org/patch/11312667/) * Add more descriptions in commit and cc to stable Fixes: ad7f8a1f9ced ("drm/helper: add Displayport multi-stream helper (v0.6)") Reviewed-by: Harry Wentland Signed-off-by: Wayne Lin Cc: stable@vger.kernel.org Signed-off-by: Lyude Paul Link: https://patchwork.freedesktop.org/patch/msgid/20200103055001.10287-1-Wayne.Lin@amd.com --- drivers/gpu/drm/drm_dp_mst_topology.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers') diff --git a/drivers/gpu/drm/drm_dp_mst_topology.c b/drivers/gpu/drm/drm_dp_mst_topology.c index 273dd80fabf3..644c72f9c594 100644 --- a/drivers/gpu/drm/drm_dp_mst_topology.c +++ b/drivers/gpu/drm/drm_dp_mst_topology.c @@ -393,7 +393,7 @@ drm_dp_encode_sideband_req(const struct drm_dp_sideband_msg_req_body *req, memcpy(&buf[idx], req->u.i2c_read.transactions[i].bytes, req->u.i2c_read.transactions[i].num_bytes); idx += req->u.i2c_read.transactions[i].num_bytes; - buf[idx] = (req->u.i2c_read.transactions[i].no_stop_bit & 0x1) << 5; + buf[idx] = (req->u.i2c_read.transactions[i].no_stop_bit & 0x1) << 4; buf[idx] |= (req->u.i2c_read.transactions[i].i2c_transaction_delay & 0xf); idx++; } -- cgit v1.2.3-59-g8ed1b From 4396393fb96449c56423fb4b351f76e45a6bcaf6 Mon Sep 17 00:00:00 2001 From: Chen-Yu Tsai Date: Tue, 7 Jan 2020 15:01:13 +0800 Subject: drm/sun4i: tcon: Set RGB DCLK min. divider based on hardware model In commit 0b8e7bbde5e7 ("drm/sun4i: tcon: Set min division of TCON0_DCLK to 1.") it was assumed that all TCON variants support a minimum divider of 1 if only DCLK was used. However, the oldest generation of hardware only supports minimum divider of 4 if only DCLK is used. If a divider of 1 was used on this old hardware, some scrolling artifact would appear. A divider of 2 seemed OK, but a divider of 3 had artifacts as well. Set the minimum divider when outputing to parallel RGB based on the hardware model, with a minimum of 4 for the oldest (A10/A10s/A13/A20) hardware, and a minimum of 1 for the rest. A value is not set for the TCON variants lacking channel 0. This fixes the scrolling artifacts seen on my A13 tablet. Fixes: 0b8e7bbde5e7 ("drm/sun4i: tcon: Set min division of TCON0_DCLK to 1.") Cc: # 5.4.x Signed-off-by: Chen-Yu Tsai Signed-off-by: Maxime Ripard Link: https://patchwork.freedesktop.org/patch/msgid/20200107070113.28951-1-wens@kernel.org --- drivers/gpu/drm/sun4i/sun4i_tcon.c | 15 ++++++++++++--- drivers/gpu/drm/sun4i/sun4i_tcon.h | 1 + 2 files changed, 13 insertions(+), 3 deletions(-) (limited to 'drivers') diff --git a/drivers/gpu/drm/sun4i/sun4i_tcon.c b/drivers/gpu/drm/sun4i/sun4i_tcon.c index 42651d737c55..c81cdce6ed55 100644 --- a/drivers/gpu/drm/sun4i/sun4i_tcon.c +++ b/drivers/gpu/drm/sun4i/sun4i_tcon.c @@ -489,7 +489,7 @@ static void sun4i_tcon0_mode_set_rgb(struct sun4i_tcon *tcon, WARN_ON(!tcon->quirks->has_channel_0); - tcon->dclk_min_div = 1; + tcon->dclk_min_div = tcon->quirks->dclk_min_div; tcon->dclk_max_div = 127; sun4i_tcon0_mode_set_common(tcon, mode); @@ -1426,12 +1426,14 @@ static int sun8i_r40_tcon_tv_set_mux(struct sun4i_tcon *tcon, static const struct sun4i_tcon_quirks sun4i_a10_quirks = { .has_channel_0 = true, .has_channel_1 = true, + .dclk_min_div = 4, .set_mux = sun4i_a10_tcon_set_mux, }; static const struct sun4i_tcon_quirks sun5i_a13_quirks = { .has_channel_0 = true, .has_channel_1 = true, + .dclk_min_div = 4, .set_mux = sun5i_a13_tcon_set_mux, }; @@ -1440,6 +1442,7 @@ static const struct sun4i_tcon_quirks sun6i_a31_quirks = { .has_channel_1 = true, .has_lvds_alt = true, .needs_de_be_mux = true, + .dclk_min_div = 1, .set_mux = sun6i_tcon_set_mux, }; @@ -1447,11 +1450,13 @@ static const struct sun4i_tcon_quirks sun6i_a31s_quirks = { .has_channel_0 = true, .has_channel_1 = true, .needs_de_be_mux = true, + .dclk_min_div = 1, }; static const struct sun4i_tcon_quirks sun7i_a20_quirks = { .has_channel_0 = true, .has_channel_1 = true, + .dclk_min_div = 4, /* Same display pipeline structure as A10 */ .set_mux = sun4i_a10_tcon_set_mux, }; @@ -1459,11 +1464,13 @@ static const struct sun4i_tcon_quirks sun7i_a20_quirks = { static const struct sun4i_tcon_quirks sun8i_a33_quirks = { .has_channel_0 = true, .has_lvds_alt = true, + .dclk_min_div = 1, }; static const struct sun4i_tcon_quirks sun8i_a83t_lcd_quirks = { .supports_lvds = true, .has_channel_0 = true, + .dclk_min_div = 1, }; static const struct sun4i_tcon_quirks sun8i_a83t_tv_quirks = { @@ -1477,11 +1484,13 @@ static const struct sun4i_tcon_quirks sun8i_r40_tv_quirks = { static const struct sun4i_tcon_quirks sun8i_v3s_quirks = { .has_channel_0 = true, + .dclk_min_div = 1, }; static const struct sun4i_tcon_quirks sun9i_a80_tcon_lcd_quirks = { - .has_channel_0 = true, - .needs_edp_reset = true, + .has_channel_0 = true, + .needs_edp_reset = true, + .dclk_min_div = 1, }; static const struct sun4i_tcon_quirks sun9i_a80_tcon_tv_quirks = { diff --git a/drivers/gpu/drm/sun4i/sun4i_tcon.h b/drivers/gpu/drm/sun4i/sun4i_tcon.h index f9f1fe80b206..a62ec826ae71 100644 --- a/drivers/gpu/drm/sun4i/sun4i_tcon.h +++ b/drivers/gpu/drm/sun4i/sun4i_tcon.h @@ -224,6 +224,7 @@ struct sun4i_tcon_quirks { bool needs_de_be_mux; /* sun6i needs mux to select backend */ bool needs_edp_reset; /* a80 edp reset needed for tcon0 access */ bool supports_lvds; /* Does the TCON support an LVDS output? */ + u8 dclk_min_div; /* minimum divider for TCON0 DCLK */ /* callback to handle tcon muxing options */ int (*set_mux)(struct sun4i_tcon *, const struct drm_encoder *); -- cgit v1.2.3-59-g8ed1b From f30e27779d3031a092c2a177b7fb76adccc45241 Mon Sep 17 00:00:00 2001 From: Geert Uytterhoeven Date: Mon, 30 Dec 2019 14:27:34 +0100 Subject: drm/fb-helper: Round up bits_per_pixel if possible When userspace requests a video mode parameter value that is not supported, frame buffer device drivers should round it up to a supported value, if possible, instead of just rejecting it. This allows applications to quickly scan for supported video modes. Currently this rule is not followed for the number of bits per pixel, causing e.g. "fbset -depth N" to fail, if N is smaller than the current number of bits per pixel. Fix this by returning an error only if bits per pixel is too large, and setting it to the current value otherwise. See also Documentation/fb/framebuffer.rst, Section 2 (Programmer's View of /dev/fb*"). Fixes: 865afb11949e5bf4 ("drm/fb-helper: reject any changes to the fbdev") Cc: stable@vger.kernel.org Signed-off-by: Geert Uytterhoeven Signed-off-by: Daniel Vetter Link: https://patchwork.freedesktop.org/patch/msgid/20191230132734.4538-1-geert+renesas@glider.be --- drivers/gpu/drm/drm_fb_helper.c | 7 ++++++- 1 file changed, 6 insertions(+), 1 deletion(-) (limited to 'drivers') diff --git a/drivers/gpu/drm/drm_fb_helper.c b/drivers/gpu/drm/drm_fb_helper.c index 8ebeccdeed23..d8e8f3960f4d 100644 --- a/drivers/gpu/drm/drm_fb_helper.c +++ b/drivers/gpu/drm/drm_fb_helper.c @@ -1283,7 +1283,7 @@ int drm_fb_helper_check_var(struct fb_var_screeninfo *var, * Changes struct fb_var_screeninfo are currently not pushed back * to KMS, hence fail if different settings are requested. */ - if (var->bits_per_pixel != fb->format->cpp[0] * 8 || + if (var->bits_per_pixel > fb->format->cpp[0] * 8 || var->xres > fb->width || var->yres > fb->height || var->xres_virtual > fb->width || var->yres_virtual > fb->height) { DRM_DEBUG("fb requested width/height/bpp can't fit in current fb " @@ -1308,6 +1308,11 @@ int drm_fb_helper_check_var(struct fb_var_screeninfo *var, drm_fb_helper_fill_pixel_fmt(var, fb->format->depth); } + /* + * Likewise, bits_per_pixel should be rounded up to a supported value. + */ + var->bits_per_pixel = fb->format->cpp[0] * 8; + /* * drm fbdev emulation doesn't support changing the pixel format at all, * so reject all pixel format changing requests. -- cgit v1.2.3-59-g8ed1b