Dne petek, 28. avgust 2020 ob 13:24:44 CEST je Ondrej Jirman napisal(a):
> It's writing too much data. regmap_bulk_write expects number of
> register sized chunks to write, not a byte sized length of the
> bounce buffer. Bounce buffer needs to be padded too, so that
> regmap_bulk_write will not read past the end of the buffer.
>
> Signed-off-by: Ondrej Jirman <meg...@megous.com>
Fixes: 133add5b5ad4 ("drm/sun4i: Add Allwinner A31 MIPI-DSI controller
support")
should be added. Fix will be then automatically picked into stable releases.
Small nit below.
> ---
> drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c | 4 ++--
> 1 file changed, 2 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c
> b/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c index 7f13f4d715bf..840fad1b68dd
> 100644
> --- a/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c
> +++ b/drivers/gpu/drm/sun4i/sun6i_mipi_dsi.c
> @@ -889,7 +889,7 @@ static int sun6i_dsi_dcs_write_long(struct sun6i_dsi
> *dsi, regmap_write(dsi->regs, SUN6I_DSI_CMD_TX_REG(0),
> sun6i_dsi_dcs_build_pkt_hdr(dsi, msg));
>
> - bounce = kzalloc(msg->tx_len + sizeof(crc), GFP_KERNEL);
> + bounce = kzalloc(msg->tx_len + sizeof(crc) + 3, GFP_KERNEL);
It would be nicer to use ALIGN() macro, but I'm fine either way.
Reviewed-by: Jernej Skrabec <jernej.skra...@siol.net>
Best regards,
Jernej
> if (!bounce)
> return -ENOMEM;
>
> @@ -900,7 +900,7 @@ static int sun6i_dsi_dcs_write_long(struct sun6i_dsi
> *dsi, memcpy((u8 *)bounce + msg->tx_len, &crc, sizeof(crc));
> len += sizeof(crc);
>
> - regmap_bulk_write(dsi->regs, SUN6I_DSI_CMD_TX_REG(1), bounce,
len);
> + regmap_bulk_write(dsi->regs, SUN6I_DSI_CMD_TX_REG(1), bounce,
> DIV_ROUND_UP(len, 4)); regmap_write(dsi->regs, SUN6I_DSI_CMD_CTL_REG, len +
> 4 - 1);
> kfree(bounce);
