[PATCH v3 2/3] drm/bridge: analogix_dp: use jiffies to simulate timeout loop
Sean Paul
seanpaul at chromium.org
Mon Sep 12 06:51:10 PDT 2016
On Fri, Sep 9, 2016 at 5:44 AM, Yakir Yang <ykk at rock-chips.com> wrote:
> Signed-off-by: Yakir Yang <ykk at rock-chips.com>
> ---
> Changes in v3:
> - Suggested by Sean
>
> Changes in v2: None
>
> drivers/gpu/drm/bridge/analogix/analogix_dp_core.h | 3 ++-
> drivers/gpu/drm/bridge/analogix/analogix_dp_reg.c | 18 +++++++++---------
> 2 files changed, 11 insertions(+), 10 deletions(-)
>
> diff --git a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.h b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.h
> index a15f076..d564e90 100644
> --- a/drivers/gpu/drm/bridge/analogix/analogix_dp_core.h
> +++ b/drivers/gpu/drm/bridge/analogix/analogix_dp_core.h
> @@ -16,10 +16,11 @@
> #include <drm/drm_crtc.h>
> #include <drm/drm_dp_helper.h>
>
> -#define DP_TIMEOUT_LOOP_COUNT 100
> #define MAX_CR_LOOP 5
> #define MAX_EQ_LOOP 5
>
> +#define DP_TIMEOUT_LOOP_MS msecs_to_jiffies(1)
The name suggests the units here are ms, but you're storing jiffies.
Do the msecs_to_jiffies conversion down below.
> +
> /* DP_MAX_LANE_COUNT */
> #define DPCD_ENHANCED_FRAME_CAP(x) (((x) >> 7) & 0x1)
> #define DPCD_MAX_LANE_COUNT(x) ((x) & 0x1f)
> diff --git a/drivers/gpu/drm/bridge/analogix/analogix_dp_reg.c b/drivers/gpu/drm/bridge/analogix/analogix_dp_reg.c
> index a4d17b8..15a4cf0 100644
> --- a/drivers/gpu/drm/bridge/analogix/analogix_dp_reg.c
> +++ b/drivers/gpu/drm/bridge/analogix/analogix_dp_reg.c
> @@ -335,7 +335,7 @@ void analogix_dp_set_analog_power_down(struct analogix_dp_device *dp,
> void analogix_dp_init_analog_func(struct analogix_dp_device *dp)
> {
> u32 reg;
> - int timeout_loop = 0;
> + unsigned long timeout;
>
> analogix_dp_set_analog_power_down(dp, POWER_ALL, 0);
>
> @@ -350,9 +350,9 @@ void analogix_dp_init_analog_func(struct analogix_dp_device *dp)
> if (analogix_dp_get_pll_lock_status(dp) == PLL_UNLOCKED) {
> analogix_dp_set_pll_power_down(dp, 0);
>
> + timeout = jiffies + DP_TIMEOUT_LOOP_MS;
timeout = jiffies + msecs_to_jiffies(DP_TIMEOUT_LOOP_MS);
> while (analogix_dp_get_pll_lock_status(dp) == PLL_UNLOCKED) {
> - timeout_loop++;
> - if (DP_TIMEOUT_LOOP_COUNT < timeout_loop) {
> + if (time_after(jiffies, timeout)) {
> dev_err(dp->dev, "failed to get pll lock status\n");
> return;
> }
> @@ -501,7 +501,7 @@ int analogix_dp_start_aux_transaction(struct analogix_dp_device *dp)
> {
> int reg;
> int retval = 0;
> - int timeout_loop = 0;
> + unsigned long timeout;
>
> /* Enable AUX CH operation */
> reg = readl(dp->reg_base + ANALOGIX_DP_AUX_CH_CTL_2);
> @@ -509,10 +509,10 @@ int analogix_dp_start_aux_transaction(struct analogix_dp_device *dp)
> writel(reg, dp->reg_base + ANALOGIX_DP_AUX_CH_CTL_2);
>
> /* Is AUX CH command reply received? */
> + timeout = jiffies + DP_TIMEOUT_LOOP_MS;
> reg = readl(dp->reg_base + ANALOGIX_DP_INT_STA);
> while (!(reg & RPLY_RECEIV)) {
> - timeout_loop++;
> - if (DP_TIMEOUT_LOOP_COUNT < timeout_loop) {
> + if (time_after(jiffies, timeout)) {
> dev_err(dp->dev, "AUX CH command reply failed!\n");
> return -ETIMEDOUT;
> }
> @@ -1055,7 +1055,7 @@ ssize_t analogix_dp_transfer(struct analogix_dp_device *dp,
> {
> u32 reg;
> u8 *buffer = msg->buffer;
> - int timeout_loop = 0;
> + unsigned long timeout;
> unsigned int i;
> int num_transferred = 0;
>
> @@ -1123,10 +1123,10 @@ ssize_t analogix_dp_transfer(struct analogix_dp_device *dp,
>
> /* Is AUX CH command reply received? */
> /* TODO: Wait for an interrupt instead of looping? */
> + timeout = jiffies + DP_TIMEOUT_LOOP_MS;
> reg = readl(dp->reg_base + ANALOGIX_DP_INT_STA);
> while (!(reg & RPLY_RECEIV)) {
> - timeout_loop++;
> - if (timeout_loop > DP_TIMEOUT_LOOP_COUNT) {
> + if (time_after(jiffies, timeout)) {
> dev_err(dp->dev, "AUX CH command reply failed!\n");
> return -ETIMEDOUT;
> }
> --
> 1.9.1
>
>
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