scsi: ufs: Make sure clk scaling happens only when HBA is runtime ACTIVE
If someone plays with the UFS clk scaling devfreq governor through sysfs, ufshcd_devfreq_scale may be called even when HBA is not runtime ACTIVE. This can lead to unexpected error. We cannot just protect it by calling pm_runtime_get_sync() because that may cause a race condition since HBA runtime suspend ops need to suspend clk scaling. To fix this call pm_runtime_get_noresume() and check HBA's runtime status. Only proceed if HBA is runtime ACTIVE, otherwise just bail. governor_store devfreq_performance_handler update_devfreq devfreq_set_target ufshcd_devfreq_target ufshcd_devfreq_scale Link: https://lore.kernel.org/r/1600758548-28576-1-git-send-email-cang@codeaurora.org Reviewed-by:Stanley Chu <stanley.chu@mediatek.com> Signed-off-by:
Can Guo <cang@codeaurora.org> Signed-off-by:
Martin K. Petersen <martin.petersen@oracle.com>
parent
1699f980
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