[PATCH v3 16/19] clk: at91: add PMC smd clock
Nicolas Ferre
nicolas.ferre at atmel.com
Tue Oct 8 12:22:22 EDT 2013
On 08/08/2013 09:17, 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 at overkiz.com>
> ---
> arch/arm/mach-at91/Kconfig | 5 ++
> drivers/clk/at91/Makefile | 1 +
> drivers/clk/at91/clk-smd.c | 171 ++++++++++++++++++++++++++++++++++++++++++++
> drivers/clk/at91/pmc.c | 7 ++
> drivers/clk/at91/pmc.h | 5 ++
> 5 files changed, 189 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..a7cf14a
> --- /dev/null
> +++ b/drivers/clk/at91/clk-smd.c
> @@ -0,0 +1,171 @@
> +/*
> + * drivers/clk/at91/clk-smd.c
> + *
> + * 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/of.h>
> +#include <linux/of_address.h>
> +#include <linux/io.h>
> +
> +#include "pmc.h"
> +
> +#define SMD_SOURCE_MAX 2
> +
> +#define to_at91sam9x5_clk_smd(hw) \
> + container_of(hw, struct at91sam9x5_clk_smd, hw)
> +struct at91sam9x5_clk_smd {
> + struct clk_hw hw;
> + struct at91_pmc *pmc;
> +};
> +
> +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) >> 8;
> + 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 > 15)
> + return *parent_rate / 16;
> +
> + 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 > 16)
> + return -EINVAL;
> + tmp = pmc_read(pmc, AT91_PMC_SMD) & ~AT91_PMC_SMD_DIV;
> + tmp |= (div - 1) << 8;
> + 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 e46de3d..0a731c8 100644
> --- a/drivers/clk/at91/pmc.c
> +++ b/drivers/clk/at91/pmc.c
> @@ -298,6 +298,13 @@ 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 b2efff5..43f2516 100644
> --- a/drivers/clk/at91/pmc.h
> +++ b/drivers/clk/at91/pmc.h
> @@ -103,4 +103,9 @@ extern void __init of_at91sam9x5_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
More information about the linux-arm-kernel
mailing list