usb: phy: omap-usb3: Improve DPLL parameter lookup code
Use a mapping table (dpll_map) to match the possible system clock rates
to the appropriate DPLL parameters.
Introduce a function "omap_usb3_get_dpll_params()" that will
return the matching DPLL parameters for the given clock rate.
Also, bail out on phy init if DPLL locking fails.
Signed-off-by: Roger Quadros <rogerq@ti.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>
diff --git a/drivers/usb/phy/phy-omap-usb3.c b/drivers/usb/phy/phy-omap-usb3.c
index a2fb30b..fc15694 100644
--- a/drivers/usb/phy/phy-omap-usb3.c
+++ b/drivers/usb/phy/phy-omap-usb3.c
@@ -27,7 +27,6 @@
#include <linux/delay.h>
#include <linux/usb/omap_control_usb.h>
-#define NUM_SYS_CLKS 6
#define PLL_STATUS 0x00000004
#define PLL_GO 0x00000008
#define PLL_CONFIGURATION1 0x0000000C
@@ -57,26 +56,32 @@
*/
# define PLL_IDLE_TIME 100;
-enum sys_clk_rate {
- CLK_RATE_UNDEFINED = -1,
- CLK_RATE_12MHZ,
- CLK_RATE_16MHZ,
- CLK_RATE_19MHZ,
- CLK_RATE_20MHZ,
- CLK_RATE_26MHZ,
- CLK_RATE_38MHZ
+struct usb_dpll_map {
+ unsigned long rate;
+ struct usb_dpll_params params;
};
-static struct usb_dpll_params omap_usb3_dpll_params[NUM_SYS_CLKS] = {
- {1250, 5, 4, 20, 0}, /* 12 MHz */
- {3125, 20, 4, 20, 0}, /* 16.8 MHz */
- {1172, 8, 4, 20, 65537}, /* 19.2 MHz */
- {1000, 7, 4, 10, 0}, /* 20 MHz */
- {1250, 12, 4, 20, 0}, /* 26 MHz */
- {3125, 47, 4, 20, 92843}, /* 38.4 MHz */
-
+static struct usb_dpll_map dpll_map[] = {
+ {12000000, {1250, 5, 4, 20, 0} }, /* 12 MHz */
+ {16800000, {3125, 20, 4, 20, 0} }, /* 16.8 MHz */
+ {19200000, {1172, 8, 4, 20, 65537} }, /* 19.2 MHz */
+ {20000000, {1000, 7, 4, 10, 0} }, /* 20 MHz */
+ {26000000, {1250, 12, 4, 20, 0} }, /* 26 MHz */
+ {38400000, {3125, 47, 4, 20, 92843} }, /* 38.4 MHz */
};
+static struct usb_dpll_params *omap_usb3_get_dpll_params(unsigned long rate)
+{
+ int i;
+
+ for (i = 0; i < ARRAY_SIZE(dpll_map); i++) {
+ if (rate == dpll_map[i].rate)
+ return &dpll_map[i].params;
+ }
+
+ return 0;
+}
+
static int omap_usb3_suspend(struct usb_phy *x, int suspend)
{
struct omap_usb *phy = phy_to_omapusb(x);
@@ -116,26 +121,6 @@
return 0;
}
-static inline enum sys_clk_rate __get_sys_clk_index(unsigned long rate)
-{
- switch (rate) {
- case 12000000:
- return CLK_RATE_12MHZ;
- case 16800000:
- return CLK_RATE_16MHZ;
- case 19200000:
- return CLK_RATE_19MHZ;
- case 20000000:
- return CLK_RATE_20MHZ;
- case 26000000:
- return CLK_RATE_26MHZ;
- case 38400000:
- return CLK_RATE_38MHZ;
- default:
- return CLK_RATE_UNDEFINED;
- }
-}
-
static void omap_usb_dpll_relock(struct omap_usb *phy)
{
u32 val;
@@ -155,39 +140,39 @@
{
u32 val;
unsigned long rate;
- enum sys_clk_rate clk_index;
+ struct usb_dpll_params *dpll_params;
- rate = clk_get_rate(phy->sys_clk);
- clk_index = __get_sys_clk_index(rate);
-
- if (clk_index == CLK_RATE_UNDEFINED) {
- pr_err("dpll cannot be locked for sys clk freq:%luHz\n", rate);
+ rate = clk_get_rate(phy->sys_clk);
+ dpll_params = omap_usb3_get_dpll_params(rate);
+ if (!dpll_params) {
+ dev_err(phy->dev,
+ "No DPLL configuration for %lu Hz SYS CLK\n", rate);
return -EINVAL;
}
val = omap_usb_readl(phy->pll_ctrl_base, PLL_CONFIGURATION1);
val &= ~PLL_REGN_MASK;
- val |= omap_usb3_dpll_params[clk_index].n << PLL_REGN_SHIFT;
+ val |= dpll_params->n << PLL_REGN_SHIFT;
omap_usb_writel(phy->pll_ctrl_base, PLL_CONFIGURATION1, val);
val = omap_usb_readl(phy->pll_ctrl_base, PLL_CONFIGURATION2);
val &= ~PLL_SELFREQDCO_MASK;
- val |= omap_usb3_dpll_params[clk_index].freq << PLL_SELFREQDCO_SHIFT;
+ val |= dpll_params->freq << PLL_SELFREQDCO_SHIFT;
omap_usb_writel(phy->pll_ctrl_base, PLL_CONFIGURATION2, val);
val = omap_usb_readl(phy->pll_ctrl_base, PLL_CONFIGURATION1);
val &= ~PLL_REGM_MASK;
- val |= omap_usb3_dpll_params[clk_index].m << PLL_REGM_SHIFT;
+ val |= dpll_params->m << PLL_REGM_SHIFT;
omap_usb_writel(phy->pll_ctrl_base, PLL_CONFIGURATION1, val);
val = omap_usb_readl(phy->pll_ctrl_base, PLL_CONFIGURATION4);
val &= ~PLL_REGM_F_MASK;
- val |= omap_usb3_dpll_params[clk_index].mf << PLL_REGM_F_SHIFT;
+ val |= dpll_params->mf << PLL_REGM_F_SHIFT;
omap_usb_writel(phy->pll_ctrl_base, PLL_CONFIGURATION4, val);
val = omap_usb_readl(phy->pll_ctrl_base, PLL_CONFIGURATION3);
val &= ~PLL_SD_MASK;
- val |= omap_usb3_dpll_params[clk_index].sd << PLL_SD_SHIFT;
+ val |= dpll_params->sd << PLL_SD_SHIFT;
omap_usb_writel(phy->pll_ctrl_base, PLL_CONFIGURATION3, val);
omap_usb_dpll_relock(phy);
@@ -198,8 +183,12 @@
static int omap_usb3_init(struct usb_phy *x)
{
struct omap_usb *phy = phy_to_omapusb(x);
+ int ret;
- omap_usb_dpll_lock(phy);
+ ret = omap_usb_dpll_lock(phy);
+ if (ret)
+ return ret;
+
omap_control_usb3_phy_power(phy->control_dev, 1);
return 0;