Re: [PATCH 1/2] ufs: core: Add quriks for VCC ramp-up delay
From: Bart Van Assche <bvanassche@acm.org>
Date: 2026-03-06 02:19:09
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On 3/5/26 6:19 PM, Ed Tsai (蔡宗軒) wrote:
On Thu, 2026-03-05 at 06:24 -0600, Bart Van Assche wrote:quoted
On 3/5/26 2:29 AM, ed.tsai@mediatek.com wrote:quoted
+ /* + * On platforms with a slow VCC ramp-up, a delay is needed after + * turning on VCC to ensure the voltage is stable before the + * reference clock is enabled. + */ + if (hba->quirks & UFSHCD_QUIRK_VCC_ON_DELAY && !ret && vcc_on && + hba->vreg_info.vcc && !hba->vreg_info.vcc->always_on) + usleep_range(1000, 1100);Since the value of the delay is platform-dependent, has it been considered to introduce a new vendor operation (vop)?A vop does feel a bit heavyweight for a simple sleep. How about we add a new configurable variable, similar to the approach used for the VCC off delay?
Let's postpone introducing such a configuration variable until there is a real need for such a configuration variable. Bart.