Remove fixed PPI lane count setup. The R-Car DSI host is capable of operating in 1..4 DSI lane mode. Remove the hard-coded 4-lane configuration from PPI register settings and instead configure the PPI lane count according to lane count information already obtained by this driver instance.

Configure TXSETR register to match PPI lane count. The R-Car V4H Reference Manual R19UH0186EJ0121 Rev.1.21 section 67.2.2.3 Tx Set Register (TXSETR), field LANECNT description indicates that the TXSETR register LANECNT bitfield lane count must be configured such, that it matches lane count configuration in PPISETR register DLEN bitfield. Make sure the LANECNT and DLEN bitfields are configured to match.

Fixes: 155358310f01 ("drm: rcar-du: Add R-Car DSI driver") Cc: stable@vger.kernel.org Signed-off-by: Marek Vasut marek.vasut+renesas@mailbox.org --- Cc: David Airlie airlied@gmail.com Cc: Geert Uytterhoeven geert+renesas@glider.be Cc: Kieran Bingham kieran.bingham+renesas@ideasonboard.com Cc: Laurent Pinchart laurent.pinchart+renesas@ideasonboard.com Cc: Maarten Lankhorst maarten.lankhorst@linux.intel.com Cc: Magnus Damm magnus.damm@gmail.com Cc: Maxime Ripard mripard@kernel.org Cc: Simona Vetter simona@ffwll.ch Cc: Thomas Zimmermann tzimmermann@suse.de Cc: Tomi Valkeinen tomi.valkeinen+renesas@ideasonboard.com Cc: dri-devel@lists.freedesktop.org Cc: linux-renesas-soc@vger.kernel.org --- V2: - Split this out of a series, update commit message, combine from drm/rcar-du: dsi: Remove fixed PPI lane count setup drm/rcar-du: dsi: Configure TXSETR register to match PPI lane count - add Fixes tag, CC stable --- drivers/gpu/drm/renesas/rcar-du/rcar_mipi_dsi.c | 5 ++++- drivers/gpu/drm/renesas/rcar-du/rcar_mipi_dsi_regs.h | 8 ++++---- 2 files changed, 8 insertions(+), 5 deletions(-)

diff --git a/drivers/gpu/drm/renesas/rcar-du/rcar_mipi_dsi.c b/drivers/gpu/drm/renesas/rcar-du/rcar_mipi_dsi.c index 1af4c73f7a88..952c3efb74da 100644 --- a/drivers/gpu/drm/renesas/rcar-du/rcar_mipi_dsi.c +++ b/drivers/gpu/drm/renesas/rcar-du/rcar_mipi_dsi.c @@ -576,7 +576,10 @@ static int rcar_mipi_dsi_startup(struct rcar_mipi_dsi *dsi, udelay(10); rcar_mipi_dsi_clr(dsi, CLOCKSET1, CLOCKSET1_UPDATEPLL);

- ppisetr = PPISETR_DLEN_3 | PPISETR_CLEN; + rcar_mipi_dsi_clr(dsi, TXSETR, TXSETR_LANECNT_MASK); + rcar_mipi_dsi_set(dsi, TXSETR, dsi->lanes - 1); + + ppisetr = ((BIT(dsi->lanes) - 1) & PPISETR_DLEN_MASK) | PPISETR_CLEN; rcar_mipi_dsi_write(dsi, PPISETR, ppisetr);

rcar_mipi_dsi_set(dsi, PHYSETUP, PHYSETUP_SHUTDOWNZ); diff --git a/drivers/gpu/drm/renesas/rcar-du/rcar_mipi_dsi_regs.h b/drivers/gpu/drm/renesas/rcar-du/rcar_mipi_dsi_regs.h index a6b276f1d6ee..a54c7eb4113b 100644 --- a/drivers/gpu/drm/renesas/rcar-du/rcar_mipi_dsi_regs.h +++ b/drivers/gpu/drm/renesas/rcar-du/rcar_mipi_dsi_regs.h @@ -12,6 +12,9 @@ #define LINKSR_LPBUSY (1 << 1) #define LINKSR_HSBUSY (1 << 0)

+#define TXSETR 0x100 +#define TXSETR_LANECNT_MASK (0x3 << 0) + /* * Video Mode Register */ @@ -80,10 +83,7 @@ * PHY-Protocol Interface (PPI) Registers */ #define PPISETR 0x700 -#define PPISETR_DLEN_0 (0x1 << 0) -#define PPISETR_DLEN_1 (0x3 << 0) -#define PPISETR_DLEN_2 (0x7 << 0) -#define PPISETR_DLEN_3 (0xf << 0) +#define PPISETR_DLEN_MASK (0xf << 0) #define PPISETR_CLEN (1 << 8)

#define PPICLCR 0x710