This mxs usbphy is only needs to be on after system boots up, and software never needs to control it anymore. Meanwhile, usbphy's parent needs to be notified if usb is suspend or not. So we design below mxs usbphy usage: - usbphy1_gate and usbphy2_gate: Their parents are dummy clock, we only needs to enable it after system boots up. - usbphy1 and usbphy2 Usage reserved bit for this clock, in that case, the refcount will be updated, but without hardware changing. Signed-off-by: Peter Chen <peter.chen@xxxxxxxxxxxxx> --- Changes for v4: - Add usbphy1_gate and usbphy2_gate to binding doc Besides, this patch will be not related with driver change anymore, so platform maintainer can queue it separately. Changes for v3: - Add new clk for usbphy clk gate which is only used at system boots up process. Changes for v2: - Use reserved bit for usb phy clk control .../devicetree/bindings/clock/imx6q-clock.txt | 2 + arch/arm/mach-imx/clk-imx6q.c | 26 ++++++++++++++++--- 2 files changed, 24 insertions(+), 4 deletions(-) diff --git a/Documentation/devicetree/bindings/clock/imx6q-clock.txt b/Documentation/devicetree/bindings/clock/imx6q-clock.txt index d77b4e6..d57ef36 100644 --- a/Documentation/devicetree/bindings/clock/imx6q-clock.txt +++ b/Documentation/devicetree/bindings/clock/imx6q-clock.txt @@ -203,6 +203,8 @@ clocks and IDs. pcie_ref 188 pcie_ref_125m 189 enet_ref 190 + usbphy1_gate 191 + usbphy2_gate 192 Examples: diff --git a/arch/arm/mach-imx/clk-imx6q.c b/arch/arm/mach-imx/clk-imx6q.c index 7f2c10c..ccb24cf 100644 --- a/arch/arm/mach-imx/clk-imx6q.c +++ b/arch/arm/mach-imx/clk-imx6q.c @@ -154,8 +154,8 @@ enum mx6q_clks { usdhc4, vdo_axi, vpu_axi, cko1, pll1_sys, pll2_bus, pll3_usb_otg, pll4_audio, pll5_video, pll8_mlb, pll7_usb_host, pll6_enet, ssi1_ipg, ssi2_ipg, ssi3_ipg, rom, usbphy1, usbphy2, ldb_di0_div_3_5, ldb_di1_div_3_5, - sata_ref, sata_ref_100m, pcie_ref, pcie_ref_125m, enet_ref, - clk_max + sata_ref, sata_ref_100m, pcie_ref, pcie_ref_125m, enet_ref, usbphy1_gate, + usbphy2_gate, clk_max }; static struct clk *clk[clk_max]; @@ -208,8 +208,21 @@ int __init mx6q_clocks_init(void) clk[pll7_usb_host] = imx_clk_pllv3(IMX_PLLV3_USB, "pll7_usb_host","osc", base + 0x20, 0x3); clk[pll8_mlb] = imx_clk_pllv3(IMX_PLLV3_MLB, "pll8_mlb", "osc", base + 0xd0, 0x0); - clk[usbphy1] = imx_clk_gate("usbphy1", "pll3_usb_otg", base + 0x10, 6); - clk[usbphy2] = imx_clk_gate("usbphy2", "pll7_usb_host", base + 0x20, 6); + /* + * Bit 20 is the reserved and read-only bit, we do this only for: + * - Do nothing for usbphy clk_enable/disable + * - Keep refcount when do usbphy clk_enable/disable, in that case, + * the clk framework may need to enable/disable usbphy's parent + */ + clk[usbphy1] = imx_clk_gate("usbphy1", "pll3_usb_otg", base + 0x10, 20); + clk[usbphy2] = imx_clk_gate("usbphy2", "pll7_usb_host", base + 0x20, 20); + + /* + * usbphy*_gate needs to be on after system boots up, and software + * never needs to control it anymore. + */ + clk[usbphy1_gate] = imx_clk_gate("usbphy1_gate", "dummy", base + 0x10, 6); + clk[usbphy2_gate] = imx_clk_gate("usbphy2_gate", "dummy", base + 0x20, 6); clk[sata_ref] = imx_clk_fixed_factor("sata_ref", "pll6_enet", 1, 5); clk[pcie_ref] = imx_clk_fixed_factor("pcie_ref", "pll6_enet", 1, 4); @@ -436,6 +449,11 @@ int __init mx6q_clocks_init(void) for (i = 0; i < ARRAY_SIZE(clks_init_on); i++) clk_prepare_enable(clk[clks_init_on[i]]); + if (IS_ENABLED(CONFIG_USB_MXS_PHY)) { + clk_prepare_enable(clk[usbphy1_gate]); + clk_prepare_enable(clk[usbphy2_gate]); + } + np = of_find_compatible_node(NULL, NULL, "fsl,imx6q-gpt"); base = of_iomap(np, 0); WARN_ON(!base); -- 1.7.0.4 -- To unsubscribe from this list: send the line "unsubscribe linux-doc" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html