diff options
Diffstat (limited to 'drivers/clk/at91/clk-usb.c')
| -rw-r--r-- | drivers/clk/at91/clk-usb.c | 398 | 
1 files changed, 398 insertions, 0 deletions
diff --git a/drivers/clk/at91/clk-usb.c b/drivers/clk/at91/clk-usb.c new file mode 100644 index 00000000000..7d1d26a4bd0 --- /dev/null +++ b/drivers/clk/at91/clk-usb.c @@ -0,0 +1,398 @@ +/* + *  Copyright (C) 2013 Boris BREZILLON <b.brezillon@overkiz.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + */ + +#include <linux/clk-provider.h> +#include <linux/clkdev.h> +#include <linux/clk/at91_pmc.h> +#include <linux/of.h> +#include <linux/of_address.h> +#include <linux/io.h> + +#include "pmc.h" + +#define USB_SOURCE_MAX		2 + +#define SAM9X5_USB_DIV_SHIFT	8 +#define SAM9X5_USB_MAX_DIV	0xf + +#define RM9200_USB_DIV_SHIFT	28 +#define RM9200_USB_DIV_TAB_SIZE	4 + +struct at91sam9x5_clk_usb { +	struct clk_hw hw; +	struct at91_pmc *pmc; +}; + +#define to_at91sam9x5_clk_usb(hw) \ +	container_of(hw, struct at91sam9x5_clk_usb, hw) + +struct at91rm9200_clk_usb { +	struct clk_hw hw; +	struct at91_pmc *pmc; +	u32 divisors[4]; +}; + +#define to_at91rm9200_clk_usb(hw) \ +	container_of(hw, struct at91rm9200_clk_usb, hw) + +static unsigned long at91sam9x5_clk_usb_recalc_rate(struct clk_hw *hw, +						    unsigned long parent_rate) +{ +	u32 tmp; +	u8 usbdiv; +	struct at91sam9x5_clk_usb *usb = to_at91sam9x5_clk_usb(hw); +	struct at91_pmc *pmc = usb->pmc; + +	tmp = pmc_read(pmc, AT91_PMC_USB); +	usbdiv = (tmp & AT91_PMC_OHCIUSBDIV) >> SAM9X5_USB_DIV_SHIFT; +	return parent_rate / (usbdiv + 1); +} + +static long at91sam9x5_clk_usb_round_rate(struct clk_hw *hw, unsigned long rate, +					  unsigned long *parent_rate) +{ +	unsigned long div; +	unsigned long bestrate; +	unsigned long tmp; + +	if (rate >= *parent_rate) +		return *parent_rate; + +	div = *parent_rate / rate; +	if (div >= SAM9X5_USB_MAX_DIV) +		return *parent_rate / (SAM9X5_USB_MAX_DIV + 1); + +	bestrate = *parent_rate / div; +	tmp = *parent_rate / (div + 1); +	if (bestrate - rate > rate - tmp) +		bestrate = tmp; + +	return bestrate; +} + +static int at91sam9x5_clk_usb_set_parent(struct clk_hw *hw, u8 index) +{ +	u32 tmp; +	struct at91sam9x5_clk_usb *usb = to_at91sam9x5_clk_usb(hw); +	struct at91_pmc *pmc = usb->pmc; + +	if (index > 1) +		return -EINVAL; +	tmp = pmc_read(pmc, AT91_PMC_USB) & ~AT91_PMC_USBS; +	if (index) +		tmp |= AT91_PMC_USBS; +	pmc_write(pmc, AT91_PMC_USB, tmp); +	return 0; +} + +static u8 at91sam9x5_clk_usb_get_parent(struct clk_hw *hw) +{ +	struct at91sam9x5_clk_usb *usb = to_at91sam9x5_clk_usb(hw); +	struct at91_pmc *pmc = usb->pmc; + +	return pmc_read(pmc, AT91_PMC_USB) & AT91_PMC_USBS; +} + +static int at91sam9x5_clk_usb_set_rate(struct clk_hw *hw, unsigned long rate, +				       unsigned long parent_rate) +{ +	u32 tmp; +	struct at91sam9x5_clk_usb *usb = to_at91sam9x5_clk_usb(hw); +	struct at91_pmc *pmc = usb->pmc; +	unsigned long div = parent_rate / rate; + +	if (parent_rate % rate || div < 1 || div >= SAM9X5_USB_MAX_DIV) +		return -EINVAL; + +	tmp = pmc_read(pmc, AT91_PMC_USB) & ~AT91_PMC_OHCIUSBDIV; +	tmp |= (div - 1) << SAM9X5_USB_DIV_SHIFT; +	pmc_write(pmc, AT91_PMC_USB, tmp); + +	return 0; +} + +static const struct clk_ops at91sam9x5_usb_ops = { +	.recalc_rate = at91sam9x5_clk_usb_recalc_rate, +	.round_rate = at91sam9x5_clk_usb_round_rate, +	.get_parent = at91sam9x5_clk_usb_get_parent, +	.set_parent = at91sam9x5_clk_usb_set_parent, +	.set_rate = at91sam9x5_clk_usb_set_rate, +}; + +static int at91sam9n12_clk_usb_enable(struct clk_hw *hw) +{ +	struct at91sam9x5_clk_usb *usb = to_at91sam9x5_clk_usb(hw); +	struct at91_pmc *pmc = usb->pmc; + +	pmc_write(pmc, AT91_PMC_USB, +		  pmc_read(pmc, AT91_PMC_USB) | AT91_PMC_USBS); +	return 0; +} + +static void at91sam9n12_clk_usb_disable(struct clk_hw *hw) +{ +	struct at91sam9x5_clk_usb *usb = to_at91sam9x5_clk_usb(hw); +	struct at91_pmc *pmc = usb->pmc; + +	pmc_write(pmc, AT91_PMC_USB, +		  pmc_read(pmc, AT91_PMC_USB) & ~AT91_PMC_USBS); +} + +static int at91sam9n12_clk_usb_is_enabled(struct clk_hw *hw) +{ +	struct at91sam9x5_clk_usb *usb = to_at91sam9x5_clk_usb(hw); +	struct at91_pmc *pmc = usb->pmc; + +	return !!(pmc_read(pmc, AT91_PMC_USB) & AT91_PMC_USBS); +} + +static const struct clk_ops at91sam9n12_usb_ops = { +	.enable = at91sam9n12_clk_usb_enable, +	.disable = at91sam9n12_clk_usb_disable, +	.is_enabled = at91sam9n12_clk_usb_is_enabled, +	.recalc_rate = at91sam9x5_clk_usb_recalc_rate, +	.round_rate = at91sam9x5_clk_usb_round_rate, +	.set_rate = at91sam9x5_clk_usb_set_rate, +}; + +static struct clk * __init +at91sam9x5_clk_register_usb(struct at91_pmc *pmc, const char *name, +			    const char **parent_names, u8 num_parents) +{ +	struct at91sam9x5_clk_usb *usb; +	struct clk *clk = NULL; +	struct clk_init_data init; + +	usb = kzalloc(sizeof(*usb), GFP_KERNEL); +	if (!usb) +		return ERR_PTR(-ENOMEM); + +	init.name = name; +	init.ops = &at91sam9x5_usb_ops; +	init.parent_names = parent_names; +	init.num_parents = num_parents; +	init.flags = CLK_SET_RATE_GATE | CLK_SET_PARENT_GATE; + +	usb->hw.init = &init; +	usb->pmc = pmc; + +	clk = clk_register(NULL, &usb->hw); +	if (IS_ERR(clk)) +		kfree(usb); + +	return clk; +} + +static struct clk * __init +at91sam9n12_clk_register_usb(struct at91_pmc *pmc, const char *name, +			     const char *parent_name) +{ +	struct at91sam9x5_clk_usb *usb; +	struct clk *clk = NULL; +	struct clk_init_data init; + +	usb = kzalloc(sizeof(*usb), GFP_KERNEL); +	if (!usb) +		return ERR_PTR(-ENOMEM); + +	init.name = name; +	init.ops = &at91sam9n12_usb_ops; +	init.parent_names = &parent_name; +	init.num_parents = 1; +	init.flags = CLK_SET_RATE_GATE; + +	usb->hw.init = &init; +	usb->pmc = pmc; + +	clk = clk_register(NULL, &usb->hw); +	if (IS_ERR(clk)) +		kfree(usb); + +	return clk; +} + +static unsigned long at91rm9200_clk_usb_recalc_rate(struct clk_hw *hw, +						    unsigned long parent_rate) +{ +	struct at91rm9200_clk_usb *usb = to_at91rm9200_clk_usb(hw); +	struct at91_pmc *pmc = usb->pmc; +	u32 tmp; +	u8 usbdiv; + +	tmp = pmc_read(pmc, AT91_CKGR_PLLBR); +	usbdiv = (tmp & AT91_PMC_USBDIV) >> RM9200_USB_DIV_SHIFT; +	if (usb->divisors[usbdiv]) +		return parent_rate / usb->divisors[usbdiv]; + +	return 0; +} + +static long at91rm9200_clk_usb_round_rate(struct clk_hw *hw, unsigned long rate, +					  unsigned long *parent_rate) +{ +	struct at91rm9200_clk_usb *usb = to_at91rm9200_clk_usb(hw); +	unsigned long bestrate = 0; +	int bestdiff = -1; +	unsigned long tmprate; +	int tmpdiff; +	int i = 0; + +	for (i = 0; i < 4; i++) { +		if (!usb->divisors[i]) +			continue; +		tmprate = *parent_rate / usb->divisors[i]; +		if (tmprate < rate) +			tmpdiff = rate - tmprate; +		else +			tmpdiff = tmprate - rate; + +		if (bestdiff < 0 || bestdiff > tmpdiff) { +			bestrate = tmprate; +			bestdiff = tmpdiff; +		} + +		if (!bestdiff) +			break; +	} + +	return bestrate; +} + +static int at91rm9200_clk_usb_set_rate(struct clk_hw *hw, unsigned long rate, +				       unsigned long parent_rate) +{ +	u32 tmp; +	int i; +	struct at91rm9200_clk_usb *usb = to_at91rm9200_clk_usb(hw); +	struct at91_pmc *pmc = usb->pmc; +	unsigned long div = parent_rate / rate; + +	if (parent_rate % rate) +		return -EINVAL; +	for (i = 0; i < RM9200_USB_DIV_TAB_SIZE; i++) { +		if (usb->divisors[i] == div) { +			tmp = pmc_read(pmc, AT91_CKGR_PLLBR) & +			      ~AT91_PMC_USBDIV; +			tmp |= i << RM9200_USB_DIV_SHIFT; +			pmc_write(pmc, AT91_CKGR_PLLBR, tmp); +			return 0; +		} +	} + +	return -EINVAL; +} + +static const struct clk_ops at91rm9200_usb_ops = { +	.recalc_rate = at91rm9200_clk_usb_recalc_rate, +	.round_rate = at91rm9200_clk_usb_round_rate, +	.set_rate = at91rm9200_clk_usb_set_rate, +}; + +static struct clk * __init +at91rm9200_clk_register_usb(struct at91_pmc *pmc, const char *name, +			    const char *parent_name, const u32 *divisors) +{ +	struct at91rm9200_clk_usb *usb; +	struct clk *clk = NULL; +	struct clk_init_data init; + +	usb = kzalloc(sizeof(*usb), GFP_KERNEL); +	if (!usb) +		return ERR_PTR(-ENOMEM); + +	init.name = name; +	init.ops = &at91rm9200_usb_ops; +	init.parent_names = &parent_name; +	init.num_parents = 1; +	init.flags = 0; + +	usb->hw.init = &init; +	usb->pmc = pmc; +	memcpy(usb->divisors, divisors, sizeof(usb->divisors)); + +	clk = clk_register(NULL, &usb->hw); +	if (IS_ERR(clk)) +		kfree(usb); + +	return clk; +} + +void __init of_at91sam9x5_clk_usb_setup(struct device_node *np, +					struct at91_pmc *pmc) +{ +	struct clk *clk; +	int i; +	int num_parents; +	const char *parent_names[USB_SOURCE_MAX]; +	const char *name = np->name; + +	num_parents = of_count_phandle_with_args(np, "clocks", "#clock-cells"); +	if (num_parents <= 0 || num_parents > USB_SOURCE_MAX) +		return; + +	for (i = 0; i < num_parents; i++) { +		parent_names[i] = of_clk_get_parent_name(np, i); +		if (!parent_names[i]) +			return; +	} + +	of_property_read_string(np, "clock-output-names", &name); + +	clk = at91sam9x5_clk_register_usb(pmc, name, parent_names, num_parents); +	if (IS_ERR(clk)) +		return; + +	of_clk_add_provider(np, of_clk_src_simple_get, clk); +} + +void __init of_at91sam9n12_clk_usb_setup(struct device_node *np, +					 struct at91_pmc *pmc) +{ +	struct clk *clk; +	const char *parent_name; +	const char *name = np->name; + +	parent_name = of_clk_get_parent_name(np, 0); +	if (!parent_name) +		return; + +	of_property_read_string(np, "clock-output-names", &name); + +	clk = at91sam9n12_clk_register_usb(pmc, name, parent_name); +	if (IS_ERR(clk)) +		return; + +	of_clk_add_provider(np, of_clk_src_simple_get, clk); +} + +void __init of_at91rm9200_clk_usb_setup(struct device_node *np, +					struct at91_pmc *pmc) +{ +	struct clk *clk; +	const char *parent_name; +	const char *name = np->name; +	u32 divisors[4] = {0, 0, 0, 0}; + +	parent_name = of_clk_get_parent_name(np, 0); +	if (!parent_name) +		return; + +	of_property_read_u32_array(np, "atmel,clk-divisors", divisors, 4); +	if (!divisors[0]) +		return; + +	of_property_read_string(np, "clock-output-names", &name); + +	clk = at91rm9200_clk_register_usb(pmc, name, parent_name, divisors); +	if (IS_ERR(clk)) +		return; + +	of_clk_add_provider(np, of_clk_src_simple_get, clk); +}  | 
