linux.git/include/linux/clk/qcom.h, branch master Linux kernel source tree clk: qcom: Add generic clkref_en support 2026-07-23T19:13:51+00:00 Qiang Yu qiang.yu@oss.qualcomm.com 2026-07-22T05:58:58+00:00 22c70e5732005356a4bc2601e7dcf878aab101e0 Before XO refclk is distributed to PCIe/USB/eDP PHYs, it passes through a QREF block. QREF is powered by dedicated LDO rails, and the clkref_en register controls whether refclk is gated through to the PHY side. These clkref controls are different from typical GCC branch clocks: - only a single enable bit is present, without branch-style config bits - regulators must be voted before enable and unvoted after disable Model this as a dedicated clk_ref clock type with custom clk_ops instead of reusing struct clk_branch semantics. Also provide a common registration/probe API so the same clkref model can be reused regardless of where clkref_en registers are placed, e.g. TCSR on glymur and TLMM on SM8750. Reviewed-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com> Signed-off-by: Qiang Yu <qiang.yu@oss.qualcomm.com> Link: https://lore.kernel.org/r/20260721-tcsr_qre_0721-v10-3-d2fa68c63b78@oss.qualcomm.com Signed-off-by: Bjorn Andersson <andersson@kernel.org> 
Before XO refclk is distributed to PCIe/USB/eDP PHYs, it passes through
a QREF block. QREF is powered by dedicated LDO rails, and the clkref_en
register controls whether refclk is gated through to the PHY side.

These clkref controls are different from typical GCC branch clocks:
- only a single enable bit is present, without branch-style config bits
- regulators must be voted before enable and unvoted after disable

Model this as a dedicated clk_ref clock type with custom clk_ops instead
of reusing struct clk_branch semantics.

Also provide a common registration/probe API so the same clkref model
can be reused regardless of where clkref_en registers are placed, e.g.
TCSR on glymur and TLMM on SM8750.

Reviewed-by: Konrad Dybcio <konrad.dybcio@oss.qualcomm.com>
Signed-off-by: Qiang Yu <qiang.yu@oss.qualcomm.com>
Link: https://lore.kernel.org/r/20260721-tcsr_qre_0721-v10-3-d2fa68c63b78@oss.qualcomm.com
Signed-off-by: Bjorn Andersson <andersson@kernel.org>