[PATCH v2 06/26] drm/rockchip: dw-mipi-dsi: fix generic packet status check
Chris Zhong
zyw at rock-chips.com
Sat Jan 21 22:24:13 PST 2017
Hi John
Reviewed-by: Chris Zhong <zyw at rock-chips.com>
On 01/22/2017 12:31 AM, John Keeping wrote:
> We want to check that both the GEN_CMD_EMPTY and GEN_PLD_W_EMPTY bits
> are set so we can't just check "val & mask" because that will be true if
> either bit is set.
According to DW mipi dsi controller databook, you are right. we should
check both the 2 BIT.
gen_pld_w_empty:
This bit indicates the empty status of the generic write payload FIFO.
Dependency : DSI_GENERIC = 1. Otherwise, this bit is reserved.
Value after reset : 0x1
> Signed-off-by: John Keeping <john at metanate.com>
> ---
> Unchanged in v2
> ---
> drivers/gpu/drm/rockchip/dw-mipi-dsi.c | 5 +++--
> 1 file changed, 3 insertions(+), 2 deletions(-)
>
> diff --git a/drivers/gpu/drm/rockchip/dw-mipi-dsi.c b/drivers/gpu/drm/rockchip/dw-mipi-dsi.c
> index 4cbbbcb619b7..4be1ff3a42bb 100644
> --- a/drivers/gpu/drm/rockchip/dw-mipi-dsi.c
> +++ b/drivers/gpu/drm/rockchip/dw-mipi-dsi.c
> @@ -545,7 +545,7 @@ static int dw_mipi_dsi_host_detach(struct mipi_dsi_host *host,
> static int dw_mipi_dsi_gen_pkt_hdr_write(struct dw_mipi_dsi *dsi, u32 hdr_val)
> {
> int ret;
> - u32 val;
> + u32 val, mask;
>
> ret = readx_poll_timeout(readl, dsi->base + DSI_CMD_PKT_STATUS,
> val, !(val & GEN_CMD_FULL), 1000,
> @@ -557,8 +557,9 @@ static int dw_mipi_dsi_gen_pkt_hdr_write(struct dw_mipi_dsi *dsi, u32 hdr_val)
>
> dsi_write(dsi, DSI_GEN_HDR, hdr_val);
>
> + mask = GEN_CMD_EMPTY | GEN_PLD_W_EMPTY;
> ret = readx_poll_timeout(readl, dsi->base + DSI_CMD_PKT_STATUS,
> - val, val & (GEN_CMD_EMPTY | GEN_PLD_W_EMPTY),
> + val, (val & mask) == mask,
> 1000, CMD_PKT_STATUS_TIMEOUT_US);
> if (ret < 0) {
> dev_err(dsi->dev, "failed to write command FIFO\n");
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