[PATCH v6 11/16] clk: at91: add PMC utmi clock
Boris BREZILLON
b.brezillon at overkiz.com
Thu Nov 28 08:39:56 EST 2013
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 at overkiz.com>
Acked-by: Nicolas Ferre <nicolas.ferre at atmel.com>
---
arch/arm/mach-at91/Kconfig | 7 ++
drivers/clk/at91/Makefile | 1 +
drivers/clk/at91/clk-utmi.c | 159 +++++++++++++++++++++++++++++++++++++++++++
drivers/clk/at91/pmc.c | 7 ++
drivers/clk/at91/pmc.h | 5 ++
5 files changed, 179 insertions(+)
create mode 100644 drivers/clk/at91/clk-utmi.c
diff --git a/arch/arm/mach-at91/Kconfig b/arch/arm/mach-at91/Kconfig
index 85b53a4..6ad37da 100644
--- 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 3873b62..a824883 100644
--- 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
index 0000000..ae3263b
--- /dev/null
+++ b/drivers/clk/at91/clk-utmi.c
@@ -0,0 +1,159 @@
+/*
+ * Copyright (C) 2013 Boris BREZILLON <b.brezillon at 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 d0a1f93..0f667fd 100644
--- a/drivers/clk/at91/pmc.c
+++ b/drivers/clk/at91/pmc.c
@@ -293,6 +293,13 @@ static const struct of_device_id pmc_clk_ids[] __initdata = {
.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 6eeed49..8e18ab0 100644
--- 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_ */
--
1.7.9.5
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