This adds a new driver for the USB PHY clocks in the CFGCHIP2 syscon register on TI DA8XX-type SoCs. The USB0 (USB 2.0) PHY clock is an interesting case because it calls clk_enable() in a reentrant way. The USB 2.0 PSC only has to be enabled temporarily while we are locking the PLL, which takes place during the clk_enable() callback. Signed-off-by: David Lechner <david@xxxxxxxxxxxxxx> --- v8 changes: - none v7 changes: - convert to platform device - rename clk local variable to usb0/usb1 - put code in da8xx-cfgchip.c instead of creating a new file v6 changes: - rename clocks to usb{0,1}_clk48 - rename USB 2.0 PSC clock to "fck" - simplify {s,g}et_parent implementations - use pr_fmt macro drivers/clk/davinci/da8xx-cfgchip.c | 351 ++++++++++++++++++++++++++++++++++++ 1 file changed, 351 insertions(+) diff --git a/drivers/clk/davinci/da8xx-cfgchip.c b/drivers/clk/davinci/da8xx-cfgchip.c index f0bdfea..858d378 100644 --- a/drivers/clk/davinci/da8xx-cfgchip.c +++ b/drivers/clk/davinci/da8xx-cfgchip.c @@ -343,6 +343,349 @@ static int __init of_da850_async3_init(struct device *dev, struct regmap *regmap return of_da8xx_cfgchip_init_mux_clock(dev, &da850_async3_info, regmap); } +/* --- USB 2.0 PHY clock --- */ + +struct da8xx_usb0_clk48 { + struct clk_hw hw; + struct clk *fck; + struct regmap *regmap; +}; + +#define to_da8xx_usb0_clk48(_hw) \ + container_of((_hw), struct da8xx_usb0_clk48, hw) + +static int da8xx_usb0_clk48_prepare(struct clk_hw *hw) +{ + struct da8xx_usb0_clk48 *usb0 = to_da8xx_usb0_clk48(hw); + + /* The USB 2.0 PSC clock is only needed temporarily during the USB 2.0 + * PHY clock enable, but since clk_prepare() can't be called in an + * atomic context (i.e. in clk_enable()), we have to prepare it here. + */ + return clk_prepare(usb0->fck); +} + +static void da8xx_usb0_clk48_unprepare(struct clk_hw *hw) +{ + struct da8xx_usb0_clk48 *usb0 = to_da8xx_usb0_clk48(hw); + + clk_unprepare(usb0->fck); +} + +static int da8xx_usb0_clk48_enable(struct clk_hw *hw) +{ + struct da8xx_usb0_clk48 *usb0 = to_da8xx_usb0_clk48(hw); + unsigned int mask, val; + int ret; + + /* Locking the USB 2.O PLL requires that the USB 2.O PSC is enabled + * temporaily. It can be turned back off once the PLL is locked. + */ + clk_enable(usb0->fck); + + /* Turn on the USB 2.0 PHY, but just the PLL, and not OTG. The USB 1.1 + * PHY may use the USB 2.0 PLL clock without USB 2.0 OTG being used. + */ + mask = CFGCHIP2_RESET | CFGCHIP2_PHYPWRDN | CFGCHIP2_PHY_PLLON; + val = CFGCHIP2_PHY_PLLON; + + regmap_write_bits(usb0->regmap, CFGCHIP(2), mask, val); + ret = regmap_read_poll_timeout(usb0->regmap, CFGCHIP(2), val, + val & CFGCHIP2_PHYCLKGD, 0, 500000); + + clk_disable(usb0->fck); + + return ret; +} + +static void da8xx_usb0_clk48_disable(struct clk_hw *hw) +{ + struct da8xx_usb0_clk48 *usb0 = to_da8xx_usb0_clk48(hw); + unsigned int val; + + val = CFGCHIP2_PHYPWRDN; + regmap_write_bits(usb0->regmap, CFGCHIP(2), val, val); +} + +static int da8xx_usb0_clk48_is_enabled(struct clk_hw *hw) +{ + struct da8xx_usb0_clk48 *usb0 = to_da8xx_usb0_clk48(hw); + unsigned int val; + + regmap_read(usb0->regmap, CFGCHIP(2), &val); + + return !!(val & CFGCHIP2_PHYCLKGD); +} + +static unsigned long da8xx_usb0_clk48_recalc_rate(struct clk_hw *hw, + unsigned long parent_rate) +{ + struct da8xx_usb0_clk48 *usb0 = to_da8xx_usb0_clk48(hw); + unsigned int mask, val; + + /* The parent clock rate must be one of the following */ + mask = CFGCHIP2_REFFREQ_MASK; + switch (parent_rate) { + case 12000000: + val = CFGCHIP2_REFFREQ_12MHZ; + break; + case 13000000: + val = CFGCHIP2_REFFREQ_13MHZ; + break; + case 19200000: + val = CFGCHIP2_REFFREQ_19_2MHZ; + break; + case 20000000: + val = CFGCHIP2_REFFREQ_20MHZ; + break; + case 24000000: + val = CFGCHIP2_REFFREQ_24MHZ; + break; + case 26000000: + val = CFGCHIP2_REFFREQ_26MHZ; + break; + case 38400000: + val = CFGCHIP2_REFFREQ_38_4MHZ; + break; + case 40000000: + val = CFGCHIP2_REFFREQ_40MHZ; + break; + case 48000000: + val = CFGCHIP2_REFFREQ_48MHZ; + break; + default: + return 0; + } + + regmap_write_bits(usb0->regmap, CFGCHIP(2), mask, val); + + /* USB 2.0 PLL always supplies 48MHz */ + return 48000000; +} + +static long da8xx_usb0_clk48_round_rate(struct clk_hw *hw, unsigned long rate, + unsigned long *parent_rate) +{ + return 48000000; +} + +static int da8xx_usb0_clk48_set_parent(struct clk_hw *hw, u8 index) +{ + struct da8xx_usb0_clk48 *usb0 = to_da8xx_usb0_clk48(hw); + + return regmap_write_bits(usb0->regmap, CFGCHIP(2), + CFGCHIP2_USB2PHYCLKMUX, + index ? CFGCHIP2_USB2PHYCLKMUX : 0); +} + +static u8 da8xx_usb0_clk48_get_parent(struct clk_hw *hw) +{ + struct da8xx_usb0_clk48 *usb0 = to_da8xx_usb0_clk48(hw); + unsigned int val; + + regmap_read(usb0->regmap, CFGCHIP(2), &val); + + return (val & CFGCHIP2_USB2PHYCLKMUX) ? 1 : 0; +} + +static const struct clk_ops da8xx_usb0_clk48_ops = { + .prepare = da8xx_usb0_clk48_prepare, + .unprepare = da8xx_usb0_clk48_unprepare, + .enable = da8xx_usb0_clk48_enable, + .disable = da8xx_usb0_clk48_disable, + .is_enabled = da8xx_usb0_clk48_is_enabled, + .recalc_rate = da8xx_usb0_clk48_recalc_rate, + .round_rate = da8xx_usb0_clk48_round_rate, + .set_parent = da8xx_usb0_clk48_set_parent, + .get_parent = da8xx_usb0_clk48_get_parent, +}; + +static struct da8xx_usb0_clk48 * +da8xx_cfgchip_register_usb0_clk48(struct device *dev, + struct regmap *regmap) +{ + const char * const parent_names[] = { "usb_refclkin", "pll0_auxclk" }; + struct clk *fck_clk; + struct da8xx_usb0_clk48 *usb0; + struct clk_init_data init; + int ret; + + fck_clk = devm_clk_get(dev, "fck"); + if (IS_ERR(fck_clk)) { + if (PTR_ERR(fck_clk) != -EPROBE_DEFER) + dev_err(dev, "Missing fck clock\n"); + return ERR_CAST(fck_clk); + } + + usb0 = devm_kzalloc(dev, sizeof(*usb0), GFP_KERNEL); + if (!usb0) + return ERR_PTR(-ENOMEM); + + init.name = "usb0_clk48"; + init.ops = &da8xx_usb0_clk48_ops; + init.parent_names = parent_names; + init.num_parents = 2; + + usb0->hw.init = &init; + usb0->fck = fck_clk; + usb0->regmap = regmap; + + ret = devm_clk_hw_register(dev, &usb0->hw); + if (ret < 0) + return ERR_PTR(ret); + + return usb0; +} + +/* --- USB 1.1 PHY clock --- */ + +struct da8xx_usb1_clk48 { + struct clk_hw hw; + struct regmap *regmap; +}; + +#define to_da8xx_usb1_clk48(_hw) \ + container_of((_hw), struct da8xx_usb1_clk48, hw) + +static int da8xx_usb1_clk48_set_parent(struct clk_hw *hw, u8 index) +{ + struct da8xx_usb1_clk48 *usb1 = to_da8xx_usb1_clk48(hw); + + return regmap_write_bits(usb1->regmap, CFGCHIP(2), + CFGCHIP2_USB1PHYCLKMUX, + index ? CFGCHIP2_USB1PHYCLKMUX : 0); +} + +static u8 da8xx_usb1_clk48_get_parent(struct clk_hw *hw) +{ + struct da8xx_usb1_clk48 *usb1 = to_da8xx_usb1_clk48(hw); + unsigned int val; + + regmap_read(usb1->regmap, CFGCHIP(2), &val); + + return (val & CFGCHIP2_USB1PHYCLKMUX) ? 1 : 0; +} + +static const struct clk_ops da8xx_usb1_clk48_ops = { + .set_parent = da8xx_usb1_clk48_set_parent, + .get_parent = da8xx_usb1_clk48_get_parent, +}; + +/** + * da8xx_cfgchip_register_usb1_clk48 - Register a new USB 1.1 PHY clock + * @regmap: The CFGCHIP regmap + */ +static struct da8xx_usb1_clk48 * +da8xx_cfgchip_register_usb1_clk48(struct device *dev, + struct regmap *regmap) +{ + const char * const parent_names[] = { "usb0_clk48", "usb_refclkin" }; + struct da8xx_usb1_clk48 *usb1; + struct clk_init_data init; + int ret; + + usb1 = devm_kzalloc(dev, sizeof(*usb1), GFP_KERNEL); + if (!usb1) + return ERR_PTR(-ENOMEM); + + init.name = "usb1_clk48"; + init.ops = &da8xx_usb1_clk48_ops; + init.parent_names = parent_names; + init.num_parents = 2; + + usb1->hw.init = &init; + usb1->regmap = regmap; + + ret = devm_clk_hw_register(dev, &usb1->hw); + if (ret < 0) + return ERR_PTR(ret); + + return usb1; +} + +static int da8xx_cfgchip_register_usb_phy_clk(struct device *dev, + struct regmap *regmap) +{ + struct da8xx_usb0_clk48 *usb0; + struct da8xx_usb1_clk48 *usb1; + struct clk_hw *parent; + + usb0 = da8xx_cfgchip_register_usb0_clk48(dev, regmap); + if (IS_ERR(usb0)) + return PTR_ERR(usb0); + + /* + * All existing boards use pll0_auxclk as the parent and new boards + * should use device tree, so hard-coding the value (1) here. + */ + parent = clk_hw_get_parent_by_index(&usb0->hw, 1); + if (parent) + clk_set_parent(usb0->hw.clk, parent->clk); + else + dev_warn(dev, "Failed to find usb0 parent clock\n"); + + usb1 = da8xx_cfgchip_register_usb1_clk48(dev, regmap); + if (IS_ERR(usb1)) + return PTR_ERR(usb1); + + /* + * All existing boards use usb0_clk48 as the parent and new boards + * should use device tree, so hard-coding the value (0) here. + */ + parent = clk_hw_get_parent_by_index(&usb1->hw, 0); + if (parent) + clk_set_parent(usb1->hw.clk, parent->clk); + else + dev_warn(dev, "Failed to find usb1 parent clock\n"); + + clk_hw_register_clkdev(&usb0->hw, "usb0_clk48", "da8xx-usb-phy"); + clk_hw_register_clkdev(&usb1->hw, "usb1_clk48", "da8xx-usb-phy"); + + return 0; +} + +static int of_da8xx_usb_phy_clk_init(struct device *dev, struct regmap *regmap) +{ + struct clk_hw_onecell_data *clk_data; + struct da8xx_usb0_clk48 *usb0; + struct da8xx_usb1_clk48 *usb1; + + clk_data = devm_kzalloc(dev, sizeof(*clk_data) + 2 * + sizeof(*clk_data->hws), GFP_KERNEL); + if (!clk_data) + return -ENOMEM; + + clk_data->num = 2; + + usb0 = da8xx_cfgchip_register_usb0_clk48(dev, regmap); + if (IS_ERR(usb0)) { + if (PTR_ERR(usb0) == -EPROBE_DEFER) + return -EPROBE_DEFER; + + dev_warn(dev, "Failed to register usb0_clk48 (%ld)\n", + PTR_ERR(usb0)); + + clk_data->hws[0] = ERR_PTR(-ENOENT); + } else { + clk_data->hws[0] = &usb0->hw; + } + + usb1 = da8xx_cfgchip_register_usb1_clk48(dev, regmap); + if (IS_ERR(usb1)) { + if (PTR_ERR(usb0) == -EPROBE_DEFER) + return -EPROBE_DEFER; + + dev_warn(dev, "Failed to register usb1_clk48 (%ld)\n", + PTR_ERR(usb1)); + + clk_data->hws[1] = ERR_PTR(-ENOENT); + } else { + clk_data->hws[1] = &usb1->hw; + } + + return devm_of_clk_add_hw_provider(dev, of_clk_hw_onecell_get, clk_data); +} + /* --- platform device --- */ static const struct of_device_id da8xx_cfgchip_of_match[] = { @@ -362,6 +705,10 @@ static const struct of_device_id da8xx_cfgchip_of_match[] = { .compatible = "ti,da850-async3-clksrc", .data = of_da850_async3_init, }, + { + .compatible = "ti,da830-usb-phy-clocks", + .data = of_da8xx_usb_phy_clk_init, + }, { } }; @@ -382,6 +729,10 @@ static const struct platform_device_id da8xx_cfgchip_id_table[] = { .name = "da850-async3-clksrc", .driver_data = (kernel_ulong_t)da850_cfgchip_register_async3, }, + { + .name = "da830-usb-phy-clks", + .driver_data = (kernel_ulong_t)da8xx_cfgchip_register_usb_phy_clk, + }, { } }; -- 2.7.4 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html