clk: at91: add PMC utmi clock

This adds new at91 utmi clock implementation using common clk framework.

This clock is a pll with a fixed factor (x40).
It is used as a source for usb clock.

Signed-off-by: Boris BREZILLON <b.brezillon@overkiz.com>
Acked-by: Mike Turquette <mturquette@linaro.org>
Signed-off-by: Nicolas Ferre <nicolas.ferre@atmel.com>

diff --git a/arch/arm/mach-at91/Kconfig b/arch/arm/mach-at91/Kconfig
index 85b53a441459eb5763110f9047882dc0d2b19b81..6ad37daca971e5beafc50302c36b11996c4ce54c 100644 (file)
--- a/arch/arm/mach-at91/Kconfig
+++ b/arch/arm/mach-at91/Kconfig
@@ -1,5 +1,8 @@
 if ARCH_AT91
 
+config HAVE_AT91_UTMI
+       bool
+
 config HAVE_AT91_DBGU0
        bool
 
@@ -78,6 +81,7 @@ config SOC_SAMA5D3
        select HAVE_FB_ATMEL
        select HAVE_AT91_DBGU1
        select AT91_USE_OLD_CLK
+       select HAVE_AT91_UTMI
        help
          Select this if you are using one of Atmel's SAMA5D3 family SoC.
          This support covers SAMA5D31, SAMA5D33, SAMA5D34, SAMA5D35.
@@ -124,6 +128,7 @@ config SOC_AT91SAM9RL
        select HAVE_FB_ATMEL
        select SOC_AT91SAM9
        select AT91_USE_OLD_CLK
+       select HAVE_AT91_UTMI
 
 config SOC_AT91SAM9G45
        bool "AT91SAM9G45 or AT91SAM9M10 families"
@@ -131,6 +136,7 @@ config SOC_AT91SAM9G45
        select HAVE_FB_ATMEL
        select SOC_AT91SAM9
        select AT91_USE_OLD_CLK
+       select HAVE_AT91_UTMI
        help
          Select this if you are using one of Atmel's AT91SAM9G45 family SoC.
          This support covers AT91SAM9G45, AT91SAM9G46, AT91SAM9M10 and AT91SAM9M11.
@@ -141,6 +147,7 @@ config SOC_AT91SAM9X5
        select HAVE_FB_ATMEL
        select SOC_AT91SAM9
        select AT91_USE_OLD_CLK
+       select HAVE_AT91_UTMI
        help
          Select this if you are using one of Atmel's AT91SAM9x5 family SoC.
          This means that your SAM9 name finishes with a '5' (except if it is

diff --git a/drivers/clk/at91/Makefile b/drivers/clk/at91/Makefile
index 3873b621768f6f5e0e74c0501caa51d9ee5d16a6..a82488323ea45b14863eb5fdf01cdd4d21747fc5 100644 (file)
--- a/drivers/clk/at91/Makefile
+++ b/drivers/clk/at91/Makefile
@@ -7,3 +7,4 @@ obj-y += clk-main.o clk-pll.o clk-plldiv.o clk-master.o
 obj-y += clk-system.o clk-peripheral.o
 
 obj-$(CONFIG_AT91_PROGRAMMABLE_CLOCKS) += clk-programmable.o
+obj-$(CONFIG_HAVE_AT91_UTMI)           += clk-utmi.o

diff --git a/drivers/clk/at91/clk-utmi.c b/drivers/clk/at91/clk-utmi.c
new file mode 100644 (file)
index 0000000..ae3263b
--- /dev/null
+++ b/drivers/clk/at91/clk-utmi.c
@@ -0,0 +1,159 @@
+/*
+ *  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/interrupt.h>
+#include <linux/irq.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/of_irq.h>
+#include <linux/io.h>
+#include <linux/sched.h>
+#include <linux/wait.h>
+
+#include "pmc.h"
+
+#define UTMI_FIXED_MUL         40
+
+struct clk_utmi {
+       struct clk_hw hw;
+       struct at91_pmc *pmc;
+       unsigned int irq;
+       wait_queue_head_t wait;
+};
+
+#define to_clk_utmi(hw) container_of(hw, struct clk_utmi, hw)
+
+static irqreturn_t clk_utmi_irq_handler(int irq, void *dev_id)
+{
+       struct clk_utmi *utmi = (struct clk_utmi *)dev_id;
+
+       wake_up(&utmi->wait);
+       disable_irq_nosync(utmi->irq);
+
+       return IRQ_HANDLED;
+}
+
+static int clk_utmi_prepare(struct clk_hw *hw)
+{
+       struct clk_utmi *utmi = to_clk_utmi(hw);
+       struct at91_pmc *pmc = utmi->pmc;
+       u32 tmp = at91_pmc_read(AT91_CKGR_UCKR) | AT91_PMC_UPLLEN |
+                 AT91_PMC_UPLLCOUNT | AT91_PMC_BIASEN;
+
+       pmc_write(pmc, AT91_CKGR_UCKR, tmp);
+
+       while (!(pmc_read(pmc, AT91_PMC_SR) & AT91_PMC_LOCKU)) {
+               enable_irq(utmi->irq);
+               wait_event(utmi->wait,
+                          pmc_read(pmc, AT91_PMC_SR) & AT91_PMC_LOCKU);
+       }
+
+       return 0;
+}
+
+static int clk_utmi_is_prepared(struct clk_hw *hw)
+{
+       struct clk_utmi *utmi = to_clk_utmi(hw);
+       struct at91_pmc *pmc = utmi->pmc;
+
+       return !!(pmc_read(pmc, AT91_PMC_SR) & AT91_PMC_LOCKU);
+}
+
+static void clk_utmi_unprepare(struct clk_hw *hw)
+{
+       struct clk_utmi *utmi = to_clk_utmi(hw);
+       struct at91_pmc *pmc = utmi->pmc;
+       u32 tmp = at91_pmc_read(AT91_CKGR_UCKR) & ~AT91_PMC_UPLLEN;
+
+       pmc_write(pmc, AT91_CKGR_UCKR, tmp);
+}
+
+static unsigned long clk_utmi_recalc_rate(struct clk_hw *hw,
+                                         unsigned long parent_rate)
+{
+       /* UTMI clk is a fixed clk multiplier */
+       return parent_rate * UTMI_FIXED_MUL;
+}
+
+static const struct clk_ops utmi_ops = {
+       .prepare = clk_utmi_prepare,
+       .unprepare = clk_utmi_unprepare,
+       .is_prepared = clk_utmi_is_prepared,
+       .recalc_rate = clk_utmi_recalc_rate,
+};
+
+static struct clk * __init
+at91_clk_register_utmi(struct at91_pmc *pmc, unsigned int irq,
+                      const char *name, const char *parent_name)
+{
+       int ret;
+       struct clk_utmi *utmi;
+       struct clk *clk = NULL;
+       struct clk_init_data init;
+
+       utmi = kzalloc(sizeof(*utmi), GFP_KERNEL);
+       if (!utmi)
+               return ERR_PTR(-ENOMEM);
+
+       init.name = name;
+       init.ops = &utmi_ops;
+       init.parent_names = parent_name ? &parent_name : NULL;
+       init.num_parents = parent_name ? 1 : 0;
+       init.flags = CLK_SET_RATE_GATE;
+
+       utmi->hw.init = &init;
+       utmi->pmc = pmc;
+       utmi->irq = irq;
+       init_waitqueue_head(&utmi->wait);
+       irq_set_status_flags(utmi->irq, IRQ_NOAUTOEN);
+       ret = request_irq(utmi->irq, clk_utmi_irq_handler,
+                         IRQF_TRIGGER_HIGH, "clk-utmi", utmi);
+       if (ret)
+               return ERR_PTR(ret);
+
+       clk = clk_register(NULL, &utmi->hw);
+       if (IS_ERR(clk))
+               kfree(utmi);
+
+       return clk;
+}
+
+static void __init
+of_at91_clk_utmi_setup(struct device_node *np, struct at91_pmc *pmc)
+{
+       unsigned int irq;
+       struct clk *clk;
+       const char *parent_name;
+       const char *name = np->name;
+
+       parent_name = of_clk_get_parent_name(np, 0);
+
+       of_property_read_string(np, "clock-output-names", &name);
+
+       irq = irq_of_parse_and_map(np, 0);
+       if (!irq)
+               return;
+
+       clk = at91_clk_register_utmi(pmc, irq, name, parent_name);
+       if (IS_ERR(clk))
+               return;
+
+       of_clk_add_provider(np, of_clk_src_simple_get, clk);
+       return;
+}
+
+void __init of_at91sam9x5_clk_utmi_setup(struct device_node *np,
+                                        struct at91_pmc *pmc)
+{
+       of_at91_clk_utmi_setup(np, pmc);
+}

diff --git a/drivers/clk/at91/pmc.c b/drivers/clk/at91/pmc.c
index d0a1f93500f0ca24f1aba743f7ad75d1a9df0adc..0f667fd4e7fab77bd0fc4e597a6f975c54c23eb3 100644 (file)
--- a/drivers/clk/at91/pmc.c
+++ b/drivers/clk/at91/pmc.c
@@ -292,6 +292,13 @@ static const struct of_device_id pmc_clk_ids[] __initdata = {
                .compatible = "atmel,at91sam9x5-clk-programmable",
                .data = of_at91sam9x5_clk_prog_setup,
        },
+#endif
+       /* UTMI clock */
+#if defined(CONFIG_HAVE_AT91_UTMI)
+       {
+               .compatible = "atmel,at91sam9x5-clk-utmi",
+               .data = of_at91sam9x5_clk_utmi_setup,
+       },
 #endif
        { /*sentinel*/ }
 };

diff --git a/drivers/clk/at91/pmc.h b/drivers/clk/at91/pmc.h
index 6eeed491c94c1922e5191a5d7ad5e411dd3970b7..8e18ab0d8e22d56b89e02752b0bc384e2e6a27e2 100644 (file)
--- a/drivers/clk/at91/pmc.h
+++ b/drivers/clk/at91/pmc.h
@@ -94,4 +94,9 @@ extern void __init of_at91sam9x5_clk_prog_setup(struct device_node *np,
                                                struct at91_pmc *pmc);
 #endif
 
+#if defined(CONFIG_HAVE_AT91_UTMI)
+extern void __init of_at91sam9x5_clk_utmi_setup(struct device_node *np,
+                                               struct at91_pmc *pmc);
+#endif
+
 #endif /* __PMC_H_ */