ARM: OMAP4: hwmod data: make 'ocp2scp_usb_phy_phy_48m" as the main clock
Kishon Vijay Abraham I [Wed, 10 Apr 2013 19:41:38 +0000 (19:41 +0000)]
Commit 92702df3570e ("ARM: OMAP4: PM: fix PM regression introduced by recent
clock cleanup") makes the 'ocp2scp_usb_phy_phy_48m' as optional
functional clock causing regression in MUSB. But this 48MHz clock is a
mandatory clock for usb phy attached to ocp2scp and hence made as the main
clock for ocp2scp.

Cc: Keerthy <j-keerthy@ti.com>
Cc: BenoƮt Cousson <b-cousson@ti.com>
Cc: Paul Walmsley <paul@pwsan.com>
Signed-off-by: Kishon Vijay Abraham I <kishon@ti.com>
[paul@pwsan.com: add comment to the hwmod data to try to prevent any
 future mistakes here]
Signed-off-by: Paul Walmsley <paul@pwsan.com>
Signed-off-by: Tony Lindgren <tony@atomide.com>

arch/arm/mach-omap2/omap_hwmod_44xx_data.c

index 9e05765..eaba9dc 100644 (file)
@@ -2714,16 +2714,22 @@ static struct omap_ocp2scp_dev ocp2scp_dev_attr[] = {
        { }
 };
 
-static struct omap_hwmod_opt_clk ocp2scp_usb_phy_opt_clks[] = {
-       { .role = "48mhz", .clk = "ocp2scp_usb_phy_phy_48m" },
-};
-
 /* ocp2scp_usb_phy */
 static struct omap_hwmod omap44xx_ocp2scp_usb_phy_hwmod = {
        .name           = "ocp2scp_usb_phy",
        .class          = &omap44xx_ocp2scp_hwmod_class,
        .clkdm_name     = "l3_init_clkdm",
-       .main_clk       = "func_48m_fclk",
+       /*
+        * ocp2scp_usb_phy_phy_48m is provided by the OMAP4 PRCM IP
+        * block as an "optional clock," and normally should never be
+        * specified as the main_clk for an OMAP IP block.  However it
+        * turns out that this clock is actually the main clock for
+        * the ocp2scp_usb_phy IP block:
+        * http://lists.infradead.org/pipermail/linux-arm-kernel/2012-September/119943.html
+        * So listing ocp2scp_usb_phy_phy_48m as a main_clk here seems
+        * to be the best workaround.
+        */
+       .main_clk       = "ocp2scp_usb_phy_phy_48m",
        .prcm = {
                .omap4 = {
                        .clkctrl_offs = OMAP4_CM_L3INIT_USBPHYOCP2SCP_CLKCTRL_OFFSET,
@@ -2732,8 +2738,6 @@ static struct omap_hwmod omap44xx_ocp2scp_usb_phy_hwmod = {
                },
        },
        .dev_attr       = ocp2scp_dev_attr,
-       .opt_clks       = ocp2scp_usb_phy_opt_clks,
-       .opt_clks_cnt   = ARRAY_SIZE(ocp2scp_usb_phy_opt_clks),
 };
 
 /*