On Wed, Jul 30, 2025 at 07:02:47PM +0200, Louis Chauvet wrote:
As stated in the AM62x Technical Reference Manual (SPRUIV7B), the data sampling edge needs to be configured in two distinct registers: one in the TIDSS IP and another in the memory-mapped control register modules. Since the latter is not within the same address range, a phandle to a syscon device is used to access the regmap.
Fixes: 32a1795f57ee ("drm/tidss: New driver for TI Keystone platform Display SubSystem") Signed-off-by: Louis Chauvet louis.chauvet@bootlin.com
Cc: stable@vger.kernel.org
Please read docs how to add stable tags.
drivers/gpu/drm/tidss/tidss_dispc.c | 14 ++++++++++++++ 1 file changed, 14 insertions(+)
diff --git a/drivers/gpu/drm/tidss/tidss_dispc.c b/drivers/gpu/drm/tidss/tidss_dispc.c index c0277fa36425ee1f966dccecf2b69a2d01794899..65ca7629a2e75437023bf58f8a1bddc24db5e3da 100644 --- a/drivers/gpu/drm/tidss/tidss_dispc.c +++ b/drivers/gpu/drm/tidss/tidss_dispc.c @@ -498,6 +498,7 @@ struct dispc_device { const struct dispc_features *feat; struct clk *fclk;
- struct regmap *clk_ctrl;
bool is_enabled; @@ -1267,6 +1268,11 @@ void dispc_vp_enable(struct dispc_device *dispc, u32 hw_videoport, FLD_VAL(mode->vdisplay - 1, 27, 16)); VP_REG_FLD_MOD(dispc, hw_videoport, DISPC_VP_CONTROL, 1, 0, 0);
- if (dispc->clk_ctrl) {
regmap_update_bits(dispc->clk_ctrl, 0, 0x100, ipc ? 0x100 : 0x000);regmap_update_bits(dispc->clk_ctrl, 0, 0x200, rf ? 0x200 : 0x000);- }
} void dispc_vp_disable(struct dispc_device *dispc, u32 hw_videoport) @@ -3012,6 +3018,14 @@ int dispc_init(struct tidss_device *tidss) dispc_init_errata(dispc);
- dispc->clk_ctrl = syscon_regmap_lookup_by_phandle_optional(tidss->dev->of_node,
"ti,clk-ctrl");- if (IS_ERR(dispc->clk_ctrl)) {
r = dev_err_probe(dispc->dev, PTR_ERR(dispc->clk_ctrl),"DISPC: syscon_regmap_lookup_by_phandle failed.\n");return r;
This breaks ABI. Commit msg mentions the reason but without justification - was everything broken? Nothing was working? Was it ever tested?
And anyway ABI impact must be clearly documented.
Best regards, Krzysztof