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 000000000000..7d1d26a4bd04 --- /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); +} |