clk: davinci: cfgchip: Add TI DA8XX USB PHY clocks

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@lechnology.com>
Signed-off-by: Stephen Boyd <sboyd@kernel.org>
This commit is contained in:
David Lechner 2018-03-15 21:52:35 -05:00 committed by Stephen Boyd
parent 1e88a8d64f
commit 58e1e2d2cd

View File

@ -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); 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 --- */ /* --- platform device --- */
static const struct of_device_id da8xx_cfgchip_of_match[] = { 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", .compatible = "ti,da850-async3-clksrc",
.data = of_da850_async3_init, .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", .name = "da850-async3-clksrc",
.driver_data = (kernel_ulong_t)da850_cfgchip_register_async3, .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,
},
{ } { }
}; };