[PATCH v2 18/22] usb: chipidea: msm: Add reset controller for PHY POR bit

Stephen Boyd
2016-07-07T22:21:09Z

The MSM chipidea wrapper has two bits that are used to reset the
first or second phy. Add support for these bits via the reset
controller framework, so that phy drivers can reset their
hardware at the right time during initialization.

Cc: Peter Chen <peter.chen@nxp.com>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Stephen Boyd <stephen.boyd@linaro.org>
---
drivers/usb/chipidea/Kconfig | 1 +
drivers/usb/chipidea/ci_hdrc_msm.c | 45 ++++++++++++++++++++++++++++++++++++--
2 files changed, 44 insertions(+), 2 deletions(-)

diff --git a/drivers/usb/chipidea/Kconfig b/drivers/usb/chipidea/Kconfig
index 4f8c342a8865..488ecdf56bdd 100644
--- a/drivers/usb/chipidea/Kconfig
+++ b/drivers/usb/chipidea/Kconfig
@@ -2,6 +2,7 @@ config USB_CHIPIDEA
tristate "ChipIdea Highspeed Dual Role Controller"
depends on ((USB_EHCI_HCD && USB_GADGET) || (USB_EHCI_HCD && !USB_GADGET) || (!USB_EHCI_HCD && USB_GADGET)) && HAS_DMA
select EXTCON
+ select RESET_CONTROLLER
help
Say Y here if your system has a dual role high speed USB
controller based on ChipIdea silicon IP. Currently, only the
diff --git a/drivers/usb/chipidea/ci_hdrc_msm.c b/drivers/usb/chipidea/ci_hdrc_msm.c
index da2d399acdd2..ab6a7713ee5c 100644
--- a/drivers/usb/chipidea/ci_hdrc_msm.c
+++ b/drivers/usb/chipidea/ci_hdrc_msm.c
@@ -14,6 +14,7 @@
#include <linux/mfd/syscon.h>
#include <linux/regmap.h>
#include <linux/io.h>
+#include <linux/reset-controller.h>
#include <linux/extcon.h>
#include <linux/of.h>

@@ -31,8 +32,10 @@
#define HSPHY_SESS_VLD_CTRL BIT(25)

/* Vendor base starts at 0x200 beyond CI base */
+#define HS_PHY_CTRL 0x0040
#define HS_PHY_SEC_CTRL 0x0078
#define HS_PHY_DIG_CLAMP_N BIT(16)
+#define HS_PHY_POR_ASSERT BIT(0)

struct ci_hdrc_msm {
struct platform_device *ci;
@@ -40,11 +43,38 @@ struct ci_hdrc_msm {
struct clk *iface_clk;
struct clk *fs_clk;
struct ci_hdrc_platform_data pdata;
+ struct reset_controller_dev rcdev;
bool secondary_phy;
bool hsic;
void __iomem *base;
};

+static int
+ci_hdrc_msm_por_reset(struct reset_controller_dev *r, unsigned long id)
+{
+ struct ci_hdrc_msm *ci_msm = container_of(r, struct ci_hdrc_msm, rcdev);
+ void __iomem *addr = ci_msm->base;
+ u32 val;
+
+ if (id)
+ addr += HS_PHY_SEC_CTRL;
+ else
+ addr += HS_PHY_CTRL;
+
+ val = readl_relaxed(addr);
+ val |= HS_PHY_POR_ASSERT;
+ writel(val, addr);
+ udelay(12);
+ val &= ~HS_PHY_POR_ASSERT;
+ writel(val, addr);
+
+ return 0;
+}
+
+static const struct reset_control_ops ci_hdrc_msm_reset_ops = {
+ .reset = ci_hdrc_msm_por_reset,
+};
+
static void ci_hdrc_msm_notify_event(struct ci_hdrc *ci, unsigned event)
{
struct device *dev = ci->dev->parent;
@@ -186,10 +216,18 @@ static int ci_hdrc_msm_probe(struct platform_device *pdev)
if (!ci->base)
return -ENOMEM;

- ret = clk_prepare_enable(ci->fs_clk);
+ ci->rcdev.owner = THIS_MODULE;
+ ci->rcdev.ops = &ci_hdrc_msm_reset_ops;
+ ci->rcdev.of_node = pdev->dev.of_node;
+ ci->rcdev.nr_resets = 2;
+ ret = reset_controller_register(&ci->rcdev);
if (ret)
return ret;

+ ret = clk_prepare_enable(ci->fs_clk);
+ if (ret)
+ goto err_fs;
+
reset_control_assert(reset);
usleep_range(10000, 12000);
reset_control_deassert(reset);
@@ -198,7 +236,7 @@ static int ci_hdrc_msm_probe(struct platform_device *pdev)

ret = clk_prepare_enable(ci->core_clk);
if (ret)
- return ret;
+ goto err_fs;

ret = clk_prepare_enable(ci->iface_clk);
if (ret)
@@ -236,6 +274,8 @@ err_mux:
clk_disable_unprepare(ci->iface_clk);
err_iface:
clk_disable_unprepare(ci->core_clk);
+err_fs:
+ reset_controller_unregister(&ci->rcdev);
return ret;
}

@@ -247,6 +287,7 @@ static int ci_hdrc_msm_remove(struct platform_device *pdev)
ci_hdrc_remove_device(ci->ci);
clk_disable_unprepare(ci->iface_clk);
clk_disable_unprepare(ci->core_clk);
+ reset_controller_unregister(&ci->rcdev);

return 0;
}
--
2.9.0.rc2.8.ga28705d