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path: root/kernel/drivers/clk/at91/clk-usb.c
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-rw-r--r--kernel/drivers/clk/at91/clk-usb.c443
1 files changed, 443 insertions, 0 deletions
diff --git a/kernel/drivers/clk/at91/clk-usb.c b/kernel/drivers/clk/at91/clk-usb.c
new file mode 100644
index 000000000..0b7c3e884
--- /dev/null
+++ b/kernel/drivers/clk/at91/clk-usb.c
@@ -0,0 +1,443 @@
+/*
+ * 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 DIV_ROUND_CLOSEST(parent_rate, (usbdiv + 1));
+}
+
+static long at91sam9x5_clk_usb_determine_rate(struct clk_hw *hw,
+ unsigned long rate,
+ unsigned long min_rate,
+ unsigned long max_rate,
+ unsigned long *best_parent_rate,
+ struct clk_hw **best_parent_hw)
+{
+ struct clk *parent = NULL;
+ long best_rate = -EINVAL;
+ unsigned long tmp_rate;
+ int best_diff = -1;
+ int tmp_diff;
+ int i;
+
+ for (i = 0; i < __clk_get_num_parents(hw->clk); i++) {
+ int div;
+
+ parent = clk_get_parent_by_index(hw->clk, i);
+ if (!parent)
+ continue;
+
+ for (div = 1; div < SAM9X5_USB_MAX_DIV + 2; div++) {
+ unsigned long tmp_parent_rate;
+
+ tmp_parent_rate = rate * div;
+ tmp_parent_rate = __clk_round_rate(parent,
+ tmp_parent_rate);
+ tmp_rate = DIV_ROUND_CLOSEST(tmp_parent_rate, div);
+ if (tmp_rate < rate)
+ tmp_diff = rate - tmp_rate;
+ else
+ tmp_diff = tmp_rate - rate;
+
+ if (best_diff < 0 || best_diff > tmp_diff) {
+ best_rate = tmp_rate;
+ best_diff = tmp_diff;
+ *best_parent_rate = tmp_parent_rate;
+ *best_parent_hw = __clk_get_hw(parent);
+ }
+
+ if (!best_diff || tmp_rate < rate)
+ break;
+ }
+
+ if (!best_diff)
+ break;
+ }
+
+ return best_rate;
+}
+
+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;
+
+ if (!rate)
+ return -EINVAL;
+
+ div = DIV_ROUND_CLOSEST(parent_rate, rate);
+ if (div > SAM9X5_USB_MAX_DIV + 1 || !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,
+ .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);
+ 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,
+ .determine_rate = at91sam9x5_clk_usb_determine_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 |
+ CLK_SET_RATE_PARENT;
+
+ 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 | CLK_SET_RATE_PARENT;
+
+ 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);
+ struct clk *parent = __clk_get_parent(hw->clk);
+ 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_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)
+{
+ u32 tmp;
+ int i;
+ struct at91rm9200_clk_usb *usb = to_at91rm9200_clk_usb(hw);
+ struct at91_pmc *pmc = usb->pmc;
+ 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) {
+ 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 = CLK_SET_RATE_PARENT;
+
+ 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);
+}