[PATCH v3 14/19] clk: at91: add PMC utmi clock
Nicolas Ferre
nicolas.ferre at atmel.com
Tue Oct 8 12:08:59 EDT 2013
On 08/08/2013 09:14, Boris BREZILLON :
> 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>
> ---
> arch/arm/mach-at91/Kconfig | 7 ++
> drivers/clk/at91/Makefile | 1 +
> drivers/clk/at91/clk-utmi.c | 161 +++++++++++++++++++++++++++++++++++++++++++
> drivers/clk/at91/pmc.c | 7 ++
> drivers/clk/at91/pmc.h | 5 ++
> 5 files changed, 181 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..244ff9e
> --- /dev/null
> +++ b/drivers/clk/at91/clk-utmi.c
> @@ -0,0 +1,161 @@
> +/*
> + * drivers/clk/at91/clk-utmi.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/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 to_clk_utmi(hw) container_of(hw, struct clk_utmi, hw)
> +
> +struct clk_utmi {
> + struct clk_hw hw;
> + struct at91_pmc *pmc;
> + unsigned int irq;
> + wait_queue_head_t wait;
> +};
> +
> +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_ready(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_disable(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)
> +{
> + return parent_rate * 40;
A constant or a little comment right here is necessary. As it is fixed
by nature, I am not against such a number, but a comment is a must for
this situation.
> +}
> +
> +static const struct clk_ops utmi_ops = {
> + .prepare = clk_utmi_prepare,
> + .is_prepared = clk_utmi_is_ready,
> + .disable = clk_utmi_disable,
> + .is_enabled = clk_utmi_is_ready,
> + .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 66a627d..238f0d2 100644
> --- a/drivers/clk/at91/pmc.c
> +++ b/drivers/clk/at91/pmc.c
> @@ -280,6 +280,13 @@ 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 5f20dc1..3ba9503 100644
> --- a/drivers/clk/at91/pmc.h
> +++ b/drivers/clk/at91/pmc.h
> @@ -91,4 +91,9 @@ 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_ */
>
--
Nicolas Ferre
More information about the linux-arm-kernel
mailing list