[RFC PATCH 08/50] ARM: at91: add PMC utmi clock
Boris BREZILLON
b.brezillon at overkiz.com
Fri Jun 7 10:24:16 EDT 2013
This is the 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>
---
arch/arm/mach-at91/Kconfig | 7 +++
drivers/clk/at91/Makefile | 1 +
drivers/clk/at91/clk-utmi.c | 114 +++++++++++++++++++++++++++++++++++++++++++
include/linux/clk/at91.h | 4 ++
4 files changed, 126 insertions(+)
diff --git a/arch/arm/mach-at91/Kconfig b/arch/arm/mach-at91/Kconfig
index 0280238..a4d442d 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
@@ -65,6 +68,7 @@ config SOC_SAMA5D3
select SOC_SAMA5
select HAVE_FB_ATMEL
select HAVE_AT91_DBGU1
+ 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.
@@ -106,12 +110,14 @@ config SOC_AT91SAM9RL
select HAVE_AT91_DBGU0
select HAVE_FB_ATMEL
select SOC_AT91SAM9
+ select HAVE_AT91_UTMI
config SOC_AT91SAM9G45
bool "AT91SAM9G45 or AT91SAM9M10 families"
select HAVE_AT91_DBGU1
select HAVE_FB_ATMEL
select SOC_AT91SAM9
+ 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.
@@ -121,6 +127,7 @@ config SOC_AT91SAM9X5
select HAVE_AT91_DBGU0
select HAVE_FB_ATMEL
select SOC_AT91SAM9
+ 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 2d7c119..76d09f0 100644
--- a/drivers/clk/at91/Makefile
+++ b/drivers/clk/at91/Makefile
@@ -6,3 +6,4 @@ 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..c0dd596
--- /dev/null
+++ b/drivers/clk/at91/clk-utmi.c
@@ -0,0 +1,114 @@
+/*
+ * drivers/clk/at91/clk-utmi.c
+ *
+ * Copyright (C) 2013 Boris BREZILLON <b.brezillon at overkiz.com>
+ *
+ * This utmiram 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.h>
+#include <linux/of.h>
+#include <linux/of_address.h>
+#include <linux/io.h>
+
+#define to_clk_utmi(hw) container_of(hw, struct clk_utmi, hw)
+
+struct clk_utmi {
+ struct clk_hw hw;
+};
+
+static int clk_utmi_prepare(struct clk_hw *hw)
+{
+ u32 tmp = at91_pmc_read(AT91_CKGR_UCKR) | AT91_PMC_UPLLEN |
+ AT91_PMC_UPLLCOUNT;
+ at91_pmc_write(AT91_CKGR_UCKR, tmp);
+ while (!(at91_pmc_read(AT91_PMC_SR) & AT91_PMC_LOCKU))
+ ;
+ return 0;
+}
+
+static int clk_utmi_is_prepared(struct clk_hw *hw)
+{
+ return !!(at91_pmc_read(AT91_PMC_SR) & AT91_PMC_LOCKU);
+}
+
+static void clk_utmi_disable(struct clk_hw *hw)
+{
+ u32 tmp = at91_pmc_read(AT91_CKGR_UCKR) & ~AT91_PMC_UPLLEN;
+ at91_pmc_write(AT91_CKGR_UCKR, tmp);
+}
+
+static unsigned long clk_utmi_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ return parent_rate * 40;
+}
+
+static const struct clk_ops utmi_ops = {
+ .prepare = clk_utmi_prepare,
+ .is_prepared = clk_utmi_is_prepared,
+ .disable = clk_utmi_disable,
+ .recalc_rate = clk_utmi_recalc_rate,
+};
+
+struct clk * __init
+at91_clk_register_utmi(const char *name, const char *parent_name)
+{
+ 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;
+
+ clk = clk_register(NULL, &utmi->hw);
+
+ if (IS_ERR(clk))
+ kfree(utmi);
+
+ return clk;
+}
+
+#if defined(CONFIG_OF)
+static void __init
+of_at91_clk_utmi_setup(struct device_node *np)
+{
+ 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);
+
+ clk = at91_clk_register_utmi(name, parent_name);
+
+ if (IS_ERR(clk))
+ return;
+
+ of_clk_add_provider(np, of_clk_src_simple_get, clk);
+ return;
+}
+
+static void __init of_at91sam9x5_clk_utmi_setup(struct device_node *np)
+{
+ of_at91_clk_utmi_setup(np);
+}
+CLK_OF_DECLARE(at91sam9x5_clk_utmi, "atmel,at91sam9x5-clk-utmi",
+ of_at91sam9x5_clk_utmi_setup);
+#endif
diff --git a/include/linux/clk/at91.h b/include/linux/clk/at91.h
index eccdf74..18c89c2 100644
--- a/include/linux/clk/at91.h
+++ b/include/linux/clk/at91.h
@@ -285,4 +285,8 @@ at91_clk_register_programmable(const char *name, const char **parent_names,
u8 num_parents, u8 id,
struct clk_programmable_layout *layout);
+
+struct clk * __init
+at91_clk_register_utmi(const char *name, const char *parent_name);
+
#endif
--
1.7.9.5
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