Re: [PATCH v4 14/17] clk: at91: add PMC smd clock
From: Nicolas Ferre
Date: Thu Oct 17 2013 - 12:27:27 EST
On 11/10/2013 13:27, Boris BREZILLON :
This patch adds at91 smd (Soft Modem) clock implementation using common clk
framework.
Not used by any driver right now.
Signed-off-by: Boris BREZILLON <b.brezillon@xxxxxxxxxxx>
Acked-by: Nicolas Ferre <nicolas.ferre@xxxxxxxxx>
---
arch/arm/mach-at91/Kconfig | 5 ++
drivers/clk/at91/Makefile | 1 +
drivers/clk/at91/clk-smd.c | 173 ++++++++++++++++++++++++++++++++++++++++++++
drivers/clk/at91/pmc.c | 7 ++
drivers/clk/at91/pmc.h | 5 ++
5 files changed, 191 insertions(+)
create mode 100644 drivers/clk/at91/clk-smd.c
diff --git a/arch/arm/mach-at91/Kconfig b/arch/arm/mach-at91/Kconfig
index b76dc4c..97033f7 100644
--- a/arch/arm/mach-at91/Kconfig
+++ b/arch/arm/mach-at91/Kconfig
@@ -39,6 +39,9 @@ config AT91_SAM9G45_RESET
config AT91_SAM9_TIME
bool
+config HAVE_AT91_SMD
+ bool
+
config SOC_AT91SAM9
bool
select AT91_SAM9_TIME
@@ -85,6 +88,7 @@ config SOC_SAMA5D3
select HAVE_AT91_DBGU1
select AT91_USE_OLD_CLK
select HAVE_AT91_UTMI
+ select HAVE_AT91_SMD
select HAVE_AT91_USB_CLK
help
Select this if you are using one of Atmel's SAMA5D3 family SoC.
@@ -157,6 +161,7 @@ config SOC_AT91SAM9X5
select SOC_AT91SAM9
select AT91_USE_OLD_CLK
select HAVE_AT91_UTMI
+ select HAVE_AT91_SMD
select HAVE_AT91_USB_CLK
help
Select this if you are using one of Atmel's AT91SAM9x5 family SoC.
diff --git a/drivers/clk/at91/Makefile b/drivers/clk/at91/Makefile
index 61db058..0e92b71 100644
--- a/drivers/clk/at91/Makefile
+++ b/drivers/clk/at91/Makefile
@@ -9,3 +9,4 @@ obj-y += clk-system.o clk-peripheral.o
obj-$(CONFIG_AT91_PROGRAMMABLE_CLOCKS) += clk-programmable.o
obj-$(CONFIG_HAVE_AT91_UTMI) += clk-utmi.o
obj-$(CONFIG_HAVE_AT91_USB_CLK) += clk-usb.o
+obj-$(CONFIG_HAVE_AT91_SMD) += clk-smd.o
diff --git a/drivers/clk/at91/clk-smd.c b/drivers/clk/at91/clk-smd.c
new file mode 100644
index 0000000..9f3fa39
--- /dev/null
+++ b/drivers/clk/at91/clk-smd.c
@@ -0,0 +1,173 @@
+/*
+ * drivers/clk/at91/clk-smd.c
+ *
+ * Copyright (C) 2013 Boris BREZILLON <b.brezillon@xxxxxxxxxxx>
+ *
+ * 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 SMD_SOURCE_MAX 2
+
+#define SMD_DIV_SHIFT 8
+#define SMD_MAX_DIV 0xf
+
+struct at91sam9x5_clk_smd {
+ struct clk_hw hw;
+ struct at91_pmc *pmc;
+};
+
+#define to_at91sam9x5_clk_smd(hw) \
+ container_of(hw, struct at91sam9x5_clk_smd, hw)
+
+static unsigned long at91sam9x5_clk_smd_recalc_rate(struct clk_hw *hw,
+ unsigned long parent_rate)
+{
+ u32 tmp;
+ u8 smddiv;
+ struct at91sam9x5_clk_smd *smd = to_at91sam9x5_clk_smd(hw);
+ struct at91_pmc *pmc = smd->pmc;
+
+ tmp = pmc_read(pmc, AT91_PMC_SMD);
+ smddiv = (tmp & AT91_PMC_SMD_DIV) >> SMD_DIV_SHIFT;
+ return parent_rate / (smddiv + 1);
+}
+
+static long at91sam9x5_clk_smd_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 > SMD_MAX_DIV)
+ return *parent_rate / (SMD_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_smd_set_parent(struct clk_hw *hw, u8 index)
+{
+ u32 tmp;
+ struct at91sam9x5_clk_smd *smd = to_at91sam9x5_clk_smd(hw);
+ struct at91_pmc *pmc = smd->pmc;
+
+ if (index > 1)
+ return -EINVAL;
+ tmp = pmc_read(pmc, AT91_PMC_SMD) & ~AT91_PMC_SMDS;
+ if (index)
+ tmp |= AT91_PMC_SMDS;
+ pmc_write(pmc, AT91_PMC_SMD, tmp);
+ return 0;
+}
+
+static u8 at91sam9x5_clk_smd_get_parent(struct clk_hw *hw)
+{
+ struct at91sam9x5_clk_smd *smd = to_at91sam9x5_clk_smd(hw);
+ struct at91_pmc *pmc = smd->pmc;
+
+ return pmc_read(pmc, AT91_PMC_SMD) & AT91_PMC_SMDS;
+}
+
+static int at91sam9x5_clk_smd_set_rate(struct clk_hw *hw, unsigned long rate,
+ unsigned long parent_rate)
+{
+ u32 tmp;
+ struct at91sam9x5_clk_smd *smd = to_at91sam9x5_clk_smd(hw);
+ struct at91_pmc *pmc = smd->pmc;
+ unsigned long div = parent_rate / rate;
+
+ if (parent_rate % rate || div < 1 || div > (SMD_MAX_DIV + 1))
+ return -EINVAL;
+ tmp = pmc_read(pmc, AT91_PMC_SMD) & ~AT91_PMC_SMD_DIV;
+ tmp |= (div - 1) << SMD_DIV_SHIFT;
+ pmc_write(pmc, AT91_PMC_SMD, tmp);
+
+ return 0;
+}
+
+static const struct clk_ops at91sam9x5_smd_ops = {
+ .recalc_rate = at91sam9x5_clk_smd_recalc_rate,
+ .round_rate = at91sam9x5_clk_smd_round_rate,
+ .get_parent = at91sam9x5_clk_smd_get_parent,
+ .set_parent = at91sam9x5_clk_smd_set_parent,
+ .set_rate = at91sam9x5_clk_smd_set_rate,
+};
+
+static struct clk * __init
+at91sam9x5_clk_register_smd(struct at91_pmc *pmc, const char *name,
+ const char **parent_names, u8 num_parents)
+{
+ struct at91sam9x5_clk_smd *smd;
+ struct clk *clk = NULL;
+ struct clk_init_data init;
+
+ smd = kzalloc(sizeof(*smd), GFP_KERNEL);
+ if (!smd)
+ return ERR_PTR(-ENOMEM);
+
+ init.name = name;
+ init.ops = &at91sam9x5_smd_ops;
+ init.parent_names = parent_names;
+ init.num_parents = num_parents;
+ init.flags = CLK_SET_RATE_GATE | CLK_SET_PARENT_GATE;
+
+ smd->hw.init = &init;
+ smd->pmc = pmc;
+
+ clk = clk_register(NULL, &smd->hw);
+ if (IS_ERR(clk))
+ kfree(smd);
+
+ return clk;
+}
+
+void __init of_at91sam9x5_clk_smd_setup(struct device_node *np,
+ struct at91_pmc *pmc)
+{
+ struct clk *clk;
+ int i;
+ int num_parents;
+ const char *parent_names[SMD_SOURCE_MAX];
+ const char *name = np->name;
+
+ num_parents = of_count_phandle_with_args(np, "clocks", "#clock-cells");
+ if (num_parents <= 0 || num_parents >= SMD_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_smd(pmc, name, parent_names,
+ num_parents);
+ if (IS_ERR(clk))
+ return;
+
+ of_clk_add_provider(np, of_clk_src_simple_get, clk);
+}
diff --git a/drivers/clk/at91/pmc.c b/drivers/clk/at91/pmc.c
index dc0b1b6..00a4a51 100644
--- a/drivers/clk/at91/pmc.c
+++ b/drivers/clk/at91/pmc.c
@@ -290,6 +290,13 @@ static const struct of_device_id pmc_clk_ids[] __initdata = {
.data = of_at91sam9x5_clk_usb_setup,
},
#endif
+ /* SMD clock */
+#if defined(CONFIG_HAVE_AT91_SMD)
+ {
+ .compatible = "atmel,at91sam9x5-clk-smd",
+ .data = of_at91sam9x5_clk_smd_setup,
+ },
+#endif
{ /*sentinel*/ }
};
diff --git a/drivers/clk/at91/pmc.h b/drivers/clk/at91/pmc.h
index eba7334..d0b8b38 100644
--- a/drivers/clk/at91/pmc.h
+++ b/drivers/clk/at91/pmc.h
@@ -105,4 +105,9 @@ extern void __init of_at91sam9n12_clk_usb_setup(struct device_node *np,
struct at91_pmc *pmc);
#endif
+#if defined(CONFIG_HAVE_AT91_SMD)
+extern void __init of_at91sam9x5_clk_smd_setup(struct device_node *np,
+ struct at91_pmc *pmc);
+#endif
+
#endif /* __PMC_H_ */
--
Nicolas Ferre
--
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