diff options
| author | Yaniv Gardi <ygardi@codeaurora.org> | 2015-03-31 14:37:14 (GMT) |
|---|---|---|
| committer | James Bottomley <JBottomley@Odin.com> | 2015-04-10 15:53:56 (GMT) |
| commit | cad2e03d8607793fd71a830b4b41fc8e9e9995ea (patch) | |
| tree | 4ffd08cf1f701eb08fab9c4c01d9d8a84386dae4 /drivers/scsi/ufs/ufshcd.c | |
| parent | bfdbe8ba21291c024afcec95b7bd515b5bf69689 (diff) | |
| download | linux-cad2e03d8607793fd71a830b4b41fc8e9e9995ea.tar.xz | |
ufs: add support to allow non standard behaviours (quirks)
Some implementation of UFS host controller HW might have some non-standard
behaviours (quirks) when compared to behaviour specified by UFSHCI
specification. This patch add support to allow specifying all such quirks
to standard UFS host controller driver so standard driver takes them into
account.
In this change a UFSHCD_QUIRK_DELAY_BEFORE_DME_CMDS is introduced,
where a minimum delay of 1ms is required before DME commands for
stability purposes.
Signed-off-by: Yaniv Gardi <ygardi@codeaurora.org>
Reviewed-by: Gilad Broner <gbroner@codeaurora.org>
Signed-off-by: James Bottomley <JBottomley@Odin.com>
Diffstat (limited to 'drivers/scsi/ufs/ufshcd.c')
| -rw-r--r-- | drivers/scsi/ufs/ufshcd.c | 35 |
1 files changed, 35 insertions, 0 deletions
diff --git a/drivers/scsi/ufs/ufshcd.c b/drivers/scsi/ufs/ufshcd.c index 5d60a86..dfd72af 100644 --- a/drivers/scsi/ufs/ufshcd.c +++ b/drivers/scsi/ufs/ufshcd.c @@ -183,6 +183,7 @@ static int __ufshcd_setup_clocks(struct ufs_hba *hba, bool on, static int ufshcd_setup_clocks(struct ufs_hba *hba, bool on); static int ufshcd_uic_hibern8_exit(struct ufs_hba *hba); static int ufshcd_uic_hibern8_enter(struct ufs_hba *hba); +static inline void ufshcd_add_delay_before_dme_cmd(struct ufs_hba *hba); static int ufshcd_host_reset_and_restore(struct ufs_hba *hba); static irqreturn_t ufshcd_intr(int irq, void *__hba); static int ufshcd_config_pwr_mode(struct ufs_hba *hba, @@ -972,6 +973,8 @@ ufshcd_send_uic_cmd(struct ufs_hba *hba, struct uic_command *uic_cmd) ufshcd_hold(hba, false); mutex_lock(&hba->uic_cmd_mutex); + ufshcd_add_delay_before_dme_cmd(hba); + spin_lock_irqsave(hba->host->host_lock, flags); ret = __ufshcd_send_uic_cmd(hba, uic_cmd); spin_unlock_irqrestore(hba->host->host_lock, flags); @@ -2058,6 +2061,37 @@ static int ufshcd_dme_link_startup(struct ufs_hba *hba) return ret; } +static inline void ufshcd_add_delay_before_dme_cmd(struct ufs_hba *hba) +{ + #define MIN_DELAY_BEFORE_DME_CMDS_US 1000 + unsigned long min_sleep_time_us; + + if (!(hba->quirks & UFSHCD_QUIRK_DELAY_BEFORE_DME_CMDS)) + return; + + /* + * last_dme_cmd_tstamp will be 0 only for 1st call to + * this function + */ + if (unlikely(!ktime_to_us(hba->last_dme_cmd_tstamp))) { + min_sleep_time_us = MIN_DELAY_BEFORE_DME_CMDS_US; + } else { + unsigned long delta = + (unsigned long) ktime_to_us( + ktime_sub(ktime_get(), + hba->last_dme_cmd_tstamp)); + + if (delta < MIN_DELAY_BEFORE_DME_CMDS_US) + min_sleep_time_us = + MIN_DELAY_BEFORE_DME_CMDS_US - delta; + else + return; /* no more delay required */ + } + + /* allow sleep for extra 50us if needed */ + usleep_range(min_sleep_time_us, min_sleep_time_us + 50); +} + /** * ufshcd_dme_set_attr - UIC command for DME_SET, DME_PEER_SET * @hba: per adapter instance @@ -2157,6 +2191,7 @@ static int ufshcd_uic_pwr_ctrl(struct ufs_hba *hba, struct uic_command *cmd) mutex_lock(&hba->uic_cmd_mutex); init_completion(&uic_async_done); + ufshcd_add_delay_before_dme_cmd(hba); spin_lock_irqsave(hba->host->host_lock, flags); hba->uic_async_done = &uic_async_done; |