The hardware initialisation register write sequence is only used at
probe. To support suspend/resume with a controller losing power, we
must redo this sequence of writes.
Extract the register write sequence to a new cdns_ti_init_hw function to
reuse it later down the road, at resume.
We keep the devicetree-parsing aspect of the sequence in probe & add a
new field in the private struct to remember the USB2 refclk rate code
computation result.
Signed-off-by: Théo Lebrun <theo.lebrun@bootlin.com>
---
drivers/usb/cdns3/cdns3-ti.c | 76 ++++++++++++++++++++++++--------------------
1 file changed, 41 insertions(+), 35 deletions(-)
@@ -57,6 +57,7 @@ struct cdns_ti {
unsigned vbus_divider:1;
struct clk *usb2_refclk;
struct clk *lpm_clk;
+ int usb2_refclk_rate_code;
};
static const int cdns_ti_rate_table[] = { /* in KHZ */
@@ -85,15 +86,50 @@ static inline void cdns_ti_writel(struct cdns_ti *data, u32 offset, u32 value)
writel(value, data->usbss + offset);
}
+static void cdns_ti_init_hw(struct cdns_ti *data)
+{
+ u32 reg;
+
+ /* assert RESET */
+ reg = cdns_ti_readl(data, USBSS_W1);
+ reg &= ~USBSS_W1_PWRUP_RST;
+ cdns_ti_writel(data, USBSS_W1, reg);
+
+ /* set static config */
+ reg = cdns_ti_readl(data, USBSS_STATIC_CONFIG);
+ reg &= ~USBSS1_STATIC_PLL_REF_SEL_MASK;
+ reg |= data->usb2_refclk_rate_code << USBSS1_STATIC_PLL_REF_SEL_SHIFT;
+
+ reg &= ~USBSS1_STATIC_VBUS_SEL_MASK;
+ if (data->vbus_divider)
+ reg |= 1 << USBSS1_STATIC_VBUS_SEL_SHIFT;
+
+ cdns_ti_writel(data, USBSS_STATIC_CONFIG, reg);
+ reg = cdns_ti_readl(data, USBSS_STATIC_CONFIG);
+
+ /* set USB2_ONLY mode if requested */
+ reg = cdns_ti_readl(data, USBSS_W1);
+ if (data->usb2_only)
+ reg |= USBSS_W1_USB2_ONLY;
+
+ /* set default modestrap */
+ reg |= USBSS_W1_MODESTRAP_SEL;
+ reg &= ~USBSS_W1_MODESTRAP_MASK;
+ reg |= USBSS_MODESTRAP_MODE_NONE << USBSS_W1_MODESTRAP_SHIFT;
+ cdns_ti_writel(data, USBSS_W1, reg);
+
+ /* de-assert RESET */
+ reg |= USBSS_W1_PWRUP_RST;
+ cdns_ti_writel(data, USBSS_W1, reg);
+}
+
static int cdns_ti_probe(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct device_node *node = pdev->dev.of_node;
struct cdns_ti *data;
- int error;
- u32 reg;
- int rate_code, i;
unsigned long rate;
+ int error, i;
data = devm_kzalloc(dev, sizeof(*data), GFP_KERNEL);
if (!data)
@@ -133,41 +169,11 @@ static int cdns_ti_probe(struct platform_device *pdev)
return -EINVAL;
}
- rate_code = i;
-
- /* assert RESET */
- reg = cdns_ti_readl(data, USBSS_W1);
- reg &= ~USBSS_W1_PWRUP_RST;
- cdns_ti_writel(data, USBSS_W1, reg);
-
- /* set static config */
- reg = cdns_ti_readl(data, USBSS_STATIC_CONFIG);
- reg &= ~USBSS1_STATIC_PLL_REF_SEL_MASK;
- reg |= rate_code << USBSS1_STATIC_PLL_REF_SEL_SHIFT;
-
- reg &= ~USBSS1_STATIC_VBUS_SEL_MASK;
+ data->usb2_refclk_rate_code = i;
data->vbus_divider = device_property_read_bool(dev, "ti,vbus-divider");
- if (data->vbus_divider)
- reg |= 1 << USBSS1_STATIC_VBUS_SEL_SHIFT;
-
- cdns_ti_writel(data, USBSS_STATIC_CONFIG, reg);
- reg = cdns_ti_readl(data, USBSS_STATIC_CONFIG);
-
- /* set USB2_ONLY mode if requested */
- reg = cdns_ti_readl(data, USBSS_W1);
data->usb2_only = device_property_read_bool(dev, "ti,usb2-only");
- if (data->usb2_only)
- reg |= USBSS_W1_USB2_ONLY;
-
- /* set default modestrap */
- reg |= USBSS_W1_MODESTRAP_SEL;
- reg &= ~USBSS_W1_MODESTRAP_MASK;
- reg |= USBSS_MODESTRAP_MODE_NONE << USBSS_W1_MODESTRAP_SHIFT;
- cdns_ti_writel(data, USBSS_W1, reg);
- /* de-assert RESET */
- reg |= USBSS_W1_PWRUP_RST;
- cdns_ti_writel(data, USBSS_W1, reg);
+ cdns_ti_init_hw(data);
error = of_platform_populate(node, NULL, NULL, dev);
if (error) {