diff options
Diffstat (limited to '')
| -rw-r--r-- | drivers/clk/at91/clk-usb.c | 465 |
1 files changed, 465 insertions, 0 deletions
diff --git a/drivers/clk/at91/clk-usb.c b/drivers/clk/at91/clk-usb.c new file mode 100644 index 000000000..6fac6383d --- /dev/null +++ b/drivers/clk/at91/clk-usb.c @@ -0,0 +1,465 @@ +/* + * 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/mfd/syscon.h> +#include <linux/regmap.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 regmap *regmap; +}; + +#define to_at91sam9x5_clk_usb(hw) \ + container_of(hw, struct at91sam9x5_clk_usb, hw) + +struct at91rm9200_clk_usb { + struct clk_hw hw; + struct regmap *regmap; + 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) +{ + struct at91sam9x5_clk_usb *usb = to_at91sam9x5_clk_usb(hw); + unsigned int usbr; + u8 usbdiv; + + regmap_read(usb->regmap, AT91_PMC_USB, &usbr); + usbdiv = (usbr & AT91_PMC_OHCIUSBDIV) >> SAM9X5_USB_DIV_SHIFT; + + return DIV_ROUND_CLOSEST(parent_rate, (usbdiv + 1)); +} + +static int at91sam9x5_clk_usb_determine_rate(struct clk_hw *hw, + struct clk_rate_request *req) +{ + struct clk_hw *parent; + long best_rate = -EINVAL; + unsigned long tmp_rate; + int best_diff = -1; + int tmp_diff; + int i; + + for (i = 0; i < clk_hw_get_num_parents(hw); i++) { + int div; + + parent = clk_hw_get_parent_by_index(hw, i); + if (!parent) + continue; + + for (div = 1; div < SAM9X5_USB_MAX_DIV + 2; div++) { + unsigned long tmp_parent_rate; + + tmp_parent_rate = req->rate * div; + tmp_parent_rate = clk_hw_round_rate(parent, + tmp_parent_rate); + if (!tmp_parent_rate) + continue; + + tmp_rate = DIV_ROUND_CLOSEST(tmp_parent_rate, div); + if (tmp_rate < req->rate) + tmp_diff = req->rate - tmp_rate; + else + tmp_diff = tmp_rate - req->rate; + + if (best_diff < 0 || best_diff > tmp_diff) { + best_rate = tmp_rate; + best_diff = tmp_diff; + req->best_parent_rate = tmp_parent_rate; + req->best_parent_hw = parent; + } + + if (!best_diff || tmp_rate < req->rate) + break; + } + + if (!best_diff) + break; + } + + if (best_rate < 0) + return best_rate; + + req->rate = best_rate; + return 0; +} + +static int at91sam9x5_clk_usb_set_parent(struct clk_hw *hw, u8 index) +{ + struct at91sam9x5_clk_usb *usb = to_at91sam9x5_clk_usb(hw); + + if (index > 1) + return -EINVAL; + + regmap_update_bits(usb->regmap, AT91_PMC_USB, AT91_PMC_USBS, + index ? AT91_PMC_USBS : 0); + + return 0; +} + +static u8 at91sam9x5_clk_usb_get_parent(struct clk_hw *hw) +{ + struct at91sam9x5_clk_usb *usb = to_at91sam9x5_clk_usb(hw); + unsigned int usbr; + + regmap_read(usb->regmap, AT91_PMC_USB, &usbr); + + return usbr & AT91_PMC_USBS; +} + +static int at91sam9x5_clk_usb_set_rate(struct clk_hw *hw, unsigned long rate, + unsigned long parent_rate) +{ + struct at91sam9x5_clk_usb *usb = to_at91sam9x5_clk_usb(hw); + unsigned long div; + + if (!rate) + return -EINVAL; + + div = DIV_ROUND_CLOSEST(parent_rate, rate); + if (div > SAM9X5_USB_MAX_DIV + 1 || !div) + return -EINVAL; + + regmap_update_bits(usb->regmap, AT91_PMC_USB, AT91_PMC_OHCIUSBDIV, + (div - 1) << SAM9X5_USB_DIV_SHIFT); + + return 0; +} + +static const struct clk_ops at91sam9x5_usb_ops = { + .recalc_rate = at91sam9x5_clk_usb_recalc_rate, + .determine_rate = at91sam9x5_clk_usb_determine_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); + + regmap_update_bits(usb->regmap, AT91_PMC_USB, AT91_PMC_USBS, + 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); + + regmap_update_bits(usb->regmap, AT91_PMC_USB, AT91_PMC_USBS, 0); +} + +static int at91sam9n12_clk_usb_is_enabled(struct clk_hw *hw) +{ + struct at91sam9x5_clk_usb *usb = to_at91sam9x5_clk_usb(hw); + unsigned int usbr; + + regmap_read(usb->regmap, AT91_PMC_USB, &usbr); + + return usbr & 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, + .determine_rate = at91sam9x5_clk_usb_determine_rate, + .set_rate = at91sam9x5_clk_usb_set_rate, +}; + +static struct clk_hw * __init +at91sam9x5_clk_register_usb(struct regmap *regmap, const char *name, + const char **parent_names, u8 num_parents) +{ + struct at91sam9x5_clk_usb *usb; + struct clk_hw *hw; + struct clk_init_data init; + int ret; + + 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 | + CLK_SET_RATE_PARENT; + + usb->hw.init = &init; + usb->regmap = regmap; + + hw = &usb->hw; + ret = clk_hw_register(NULL, &usb->hw); + if (ret) { + kfree(usb); + hw = ERR_PTR(ret); + } + + return hw; +} + +static struct clk_hw * __init +at91sam9n12_clk_register_usb(struct regmap *regmap, const char *name, + const char *parent_name) +{ + struct at91sam9x5_clk_usb *usb; + struct clk_hw *hw; + struct clk_init_data init; + int ret; + + 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 | CLK_SET_RATE_PARENT; + + usb->hw.init = &init; + usb->regmap = regmap; + + hw = &usb->hw; + ret = clk_hw_register(NULL, &usb->hw); + if (ret) { + kfree(usb); + hw = ERR_PTR(ret); + } + + return hw; +} + +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); + unsigned int pllbr; + u8 usbdiv; + + regmap_read(usb->regmap, AT91_CKGR_PLLBR, &pllbr); + + usbdiv = (pllbr & 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); + struct clk_hw *parent = clk_hw_get_parent(hw); + unsigned long bestrate = 0; + int bestdiff = -1; + unsigned long tmprate; + int tmpdiff; + int i = 0; + + for (i = 0; i < RM9200_USB_DIV_TAB_SIZE; i++) { + unsigned long tmp_parent_rate; + + if (!usb->divisors[i]) + continue; + + tmp_parent_rate = rate * usb->divisors[i]; + tmp_parent_rate = clk_hw_round_rate(parent, tmp_parent_rate); + tmprate = DIV_ROUND_CLOSEST(tmp_parent_rate, usb->divisors[i]); + if (tmprate < rate) + tmpdiff = rate - tmprate; + else + tmpdiff = tmprate - rate; + + if (bestdiff < 0 || bestdiff > tmpdiff) { + bestrate = tmprate; + bestdiff = tmpdiff; + *parent_rate = tmp_parent_rate; + } + + if (!bestdiff) + break; + } + + return bestrate; +} + +static int at91rm9200_clk_usb_set_rate(struct clk_hw *hw, unsigned long rate, + unsigned long parent_rate) +{ + int i; + struct at91rm9200_clk_usb *usb = to_at91rm9200_clk_usb(hw); + unsigned long div; + + if (!rate) + return -EINVAL; + + div = DIV_ROUND_CLOSEST(parent_rate, rate); + + for (i = 0; i < RM9200_USB_DIV_TAB_SIZE; i++) { + if (usb->divisors[i] == div) { + regmap_update_bits(usb->regmap, AT91_CKGR_PLLBR, + AT91_PMC_USBDIV, + i << RM9200_USB_DIV_SHIFT); + + 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_hw * __init +at91rm9200_clk_register_usb(struct regmap *regmap, const char *name, + const char *parent_name, const u32 *divisors) +{ + struct at91rm9200_clk_usb *usb; + struct clk_hw *hw; + struct clk_init_data init; + int ret; + + 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 = CLK_SET_RATE_PARENT; + + usb->hw.init = &init; + usb->regmap = regmap; + memcpy(usb->divisors, divisors, sizeof(usb->divisors)); + + hw = &usb->hw; + ret = clk_hw_register(NULL, &usb->hw); + if (ret) { + kfree(usb); + hw = ERR_PTR(ret); + } + + return hw; +} + +static void __init of_at91sam9x5_clk_usb_setup(struct device_node *np) +{ + struct clk_hw *hw; + unsigned int num_parents; + const char *parent_names[USB_SOURCE_MAX]; + const char *name = np->name; + struct regmap *regmap; + + num_parents = of_clk_get_parent_count(np); + if (num_parents == 0 || num_parents > USB_SOURCE_MAX) + return; + + of_clk_parent_fill(np, parent_names, num_parents); + + of_property_read_string(np, "clock-output-names", &name); + + regmap = syscon_node_to_regmap(of_get_parent(np)); + if (IS_ERR(regmap)) + return; + + hw = at91sam9x5_clk_register_usb(regmap, name, parent_names, + num_parents); + if (IS_ERR(hw)) + return; + + of_clk_add_hw_provider(np, of_clk_hw_simple_get, hw); +} +CLK_OF_DECLARE(at91sam9x5_clk_usb, "atmel,at91sam9x5-clk-usb", + of_at91sam9x5_clk_usb_setup); + +static void __init of_at91sam9n12_clk_usb_setup(struct device_node *np) +{ + struct clk_hw *hw; + const char *parent_name; + const char *name = np->name; + struct regmap *regmap; + + parent_name = of_clk_get_parent_name(np, 0); + if (!parent_name) + return; + + of_property_read_string(np, "clock-output-names", &name); + + regmap = syscon_node_to_regmap(of_get_parent(np)); + if (IS_ERR(regmap)) + return; + + hw = at91sam9n12_clk_register_usb(regmap, name, parent_name); + if (IS_ERR(hw)) + return; + + of_clk_add_hw_provider(np, of_clk_hw_simple_get, hw); +} +CLK_OF_DECLARE(at91sam9n12_clk_usb, "atmel,at91sam9n12-clk-usb", + of_at91sam9n12_clk_usb_setup); + +static void __init of_at91rm9200_clk_usb_setup(struct device_node *np) +{ + struct clk_hw *hw; + const char *parent_name; + const char *name = np->name; + u32 divisors[4] = {0, 0, 0, 0}; + struct regmap *regmap; + + 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); + + regmap = syscon_node_to_regmap(of_get_parent(np)); + if (IS_ERR(regmap)) + return; + hw = at91rm9200_clk_register_usb(regmap, name, parent_name, divisors); + if (IS_ERR(hw)) + return; + + of_clk_add_hw_provider(np, of_clk_hw_simple_get, hw); +} +CLK_OF_DECLARE(at91rm9200_clk_usb, "atmel,at91rm9200-clk-usb", + of_at91rm9200_clk_usb_setup); |