linux-stable/drivers/clocksource/armv7m_systick.c
Daniel Lezcano 177cf6e52b clocksources: Switch back to the clksrc table
All the clocksource drivers's init function are now converted to return
an error code. CLOCKSOURCE_OF_DECLARE is no longer used as well as the
clksrc-of table.

Let's convert back the names:
 - CLOCKSOURCE_OF_DECLARE_RET => CLOCKSOURCE_OF_DECLARE
 - clksrc-of-ret              => clksrc-of

Signed-off-by: Daniel Lezcano <daniel.lezcano@linaro.org>

For exynos_mct and samsung_pwm_timer:
Acked-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>

For arch/arc:
Acked-by: Vineet Gupta <vgupta@synopsys.com>

For mediatek driver:
Acked-by: Matthias Brugger <matthias.bgg@gmail.com>

For the Rockchip-part
Acked-by: Heiko Stuebner <heiko@sntech.de>

For STi :
Acked-by: Patrice Chotard <patrice.chotard@st.com>

For the mps2-timer.c and versatile.c changes:
Acked-by: Liviu Dudau <Liviu.Dudau@arm.com>

For the OXNAS part :
Acked-by: Neil Armstrong <narmstrong@baylibre.com>

For LPC32xx driver:
Acked-by: Sylvain Lemieux <slemieux.tyco@gmail.com>

For Broadcom Kona timer change:
Acked-by: Ray Jui <ray.jui@broadcom.com>

For Sun4i and Sun5i:
Acked-by: Chen-Yu Tsai <wens@csie.org>

For Meson6:
Acked-by: Carlo Caione <carlo@caione.org>

For Keystone:
Acked-by: Santosh Shilimkar <ssantosh@kernel.org>

For NPS:
Acked-by: Noam Camus <noamca@mellanox.com>

For bcm2835:
Acked-by: Eric Anholt <eric@anholt.net>
2016-06-28 10:19:35 +02:00

85 lines
1.7 KiB
C

/*
* Copyright (C) Maxime Coquelin 2015
* Author: Maxime Coquelin <mcoquelin.stm32@gmail.com>
* License terms: GNU General Public License (GPL), version 2
*/
#include <linux/kernel.h>
#include <linux/clocksource.h>
#include <linux/clockchips.h>
#include <linux/of.h>
#include <linux/of_address.h>
#include <linux/clk.h>
#include <linux/bitops.h>
#define SYST_CSR 0x00
#define SYST_RVR 0x04
#define SYST_CVR 0x08
#define SYST_CALIB 0x0c
#define SYST_CSR_ENABLE BIT(0)
#define SYSTICK_LOAD_RELOAD_MASK 0x00FFFFFF
static int __init system_timer_of_register(struct device_node *np)
{
struct clk *clk = NULL;
void __iomem *base;
u32 rate;
int ret;
base = of_iomap(np, 0);
if (!base) {
pr_warn("system-timer: invalid base address\n");
return -ENXIO;
}
ret = of_property_read_u32(np, "clock-frequency", &rate);
if (ret) {
clk = of_clk_get(np, 0);
if (IS_ERR(clk)) {
ret = PTR_ERR(clk);
goto out_unmap;
}
ret = clk_prepare_enable(clk);
if (ret)
goto out_clk_put;
rate = clk_get_rate(clk);
if (!rate) {
ret = -EINVAL;
goto out_clk_disable;
}
}
writel_relaxed(SYSTICK_LOAD_RELOAD_MASK, base + SYST_RVR);
writel_relaxed(SYST_CSR_ENABLE, base + SYST_CSR);
ret = clocksource_mmio_init(base + SYST_CVR, "arm_system_timer", rate,
200, 24, clocksource_mmio_readl_down);
if (ret) {
pr_err("failed to init clocksource (%d)\n", ret);
if (clk)
goto out_clk_disable;
else
goto out_unmap;
}
pr_info("ARM System timer initialized as clocksource\n");
return 0;
out_clk_disable:
clk_disable_unprepare(clk);
out_clk_put:
clk_put(clk);
out_unmap:
iounmap(base);
pr_warn("ARM System timer register failed (%d)\n", ret);
return ret;
}
CLOCKSOURCE_OF_DECLARE(arm_systick, "arm,armv7m-systick",
system_timer_of_register);