Commit 5dd65cf7 authored by Arnd Bergmann's avatar Arnd Bergmann
Browse files

Merge tag 'reset-for-v5.11' of git://git.pengutronix.de/pza/linux into arm/drivers 

Reset controller updates for v5.11

This tag adds support for sharing pulsed resets under certain
conditions. For example, when multiple drivers go through a
suspend-resume cycle, a reset line they share can be triggered
again during resume.
Further, the reset-meson driver now can be built as a module, the
reset-socfpga driver properly releases its memory region in the
probe error path, and reset-ti-syscon driver uses regmap_write_bits()
instead of regmap_update_bits() to support devices without status
readback.

* tag 'reset-for-v5.11' of git://git.pengutronix.de/pza/linux:
  reset-controller: ti: force the write operation when assert or deassert
  reset: socfpga: add error handling and release mem-region
  reset: meson: make it possible to build as a module
  reset: make shared pulsed reset controls re-triggerable

Link: https://lore.kernel.org/r/d586ada0073f2ac50a02274f42bf07bfb0603835.camel@pengutronix.de


Signed-off-by: default avatarArnd Bergmann <arnd@arndb.de>
parents e0839f3e d06c4dec

drivers/reset/Kconfig

+2 −1
Original line number Diff line number Diff line
@@ -95,7 +95,8 @@ config RESET_LPC18XX 
	  This enables the reset controller driver for NXP LPC18xx/43xx SoCs.



config RESET_MESON

	bool "Meson Reset Driver" if COMPILE_TEST

	tristate "Meson Reset Driver"

	depends on ARCH_MESON || COMPILE_TEST

	default ARCH_MESON

	help

	  This enables the reset driver for Amlogic Meson SoCs.

drivers/reset/core.c

+73 −0
Original line number Diff line number Diff line
@@ -208,6 +208,39 @@ static int reset_control_array_reset(struct reset_control_array *resets) 
	return 0;

}



static int reset_control_array_rearm(struct reset_control_array *resets)

{

	struct reset_control *rstc;

	int i;



	for (i = 0; i < resets->num_rstcs; i++) {

		rstc = resets->rstc[i];



		if (!rstc)

			continue;



		if (WARN_ON(IS_ERR(rstc)))

			return -EINVAL;



		if (rstc->shared) {

			if (WARN_ON(atomic_read(&rstc->deassert_count) != 0))

				return -EINVAL;

		} else {

			if (!rstc->acquired)

				return -EPERM;

		}

	}



	for (i = 0; i < resets->num_rstcs; i++) {

		rstc = resets->rstc[i];



		if (rstc && rstc->shared)

			WARN_ON(atomic_dec_return(&rstc->triggered_count) < 0);

	}



	return 0;

}



static int reset_control_array_assert(struct reset_control_array *resets)

{

	int ret, i;
@@ -325,6 +358,46 @@ int reset_control_reset(struct reset_control *rstc) 
}

EXPORT_SYMBOL_GPL(reset_control_reset);



/**

 * reset_control_rearm - allow shared reset line to be re-triggered"

 * @rstc: reset controller

 *

 * On a shared reset line the actual reset pulse is only triggered once for the

 * lifetime of the reset_control instance, except if this call is used.

 *

 * Calls to this function must be balanced with calls to reset_control_reset,

 * a warning is thrown in case triggered_count ever dips below 0.

 *

 * Consumers must not use reset_control_(de)assert on shared reset lines when

 * reset_control_reset or reset_control_rearm have been used.

 *

 * If rstc is NULL the function will just return 0.

 */

int reset_control_rearm(struct reset_control *rstc)

{

	if (!rstc)

		return 0;



	if (WARN_ON(IS_ERR(rstc)))

		return -EINVAL;



	if (reset_control_is_array(rstc))

		return reset_control_array_rearm(rstc_to_array(rstc));



	if (rstc->shared) {

		if (WARN_ON(atomic_read(&rstc->deassert_count) != 0))

			return -EINVAL;



		WARN_ON(atomic_dec_return(&rstc->triggered_count) < 0);

	} else {

		if (!rstc->acquired)

			return -EPERM;

	}



	return 0;

}

EXPORT_SYMBOL_GPL(reset_control_rearm);



/**

 * reset_control_assert - asserts the reset line

 * @rstc: reset controller

drivers/reset/reset-meson.c

+7 −1
Original line number Diff line number Diff line
@@ -9,6 +9,7 @@ 
#include <linux/init.h>

#include <linux/io.h>

#include <linux/of.h>

#include <linux/module.h>

#include <linux/platform_device.h>

#include <linux/reset-controller.h>

#include <linux/slab.h>
@@ -104,6 +105,7 @@ static const struct of_device_id meson_reset_dt_ids[] = { 
	 { .compatible = "amlogic,meson-a1-reset",   .data = &meson_a1_param},

	 { /* sentinel */ },

};

MODULE_DEVICE_TABLE(of, meson_reset_dt_ids);



static int meson_reset_probe(struct platform_device *pdev)

{
@@ -142,4 +144,8 @@ static struct platform_driver meson_reset_driver = { 
		.of_match_table	= meson_reset_dt_ids,

	},

};

builtin_platform_driver(meson_reset_driver);
 
module_platform_driver(meson_reset_driver);



MODULE_DESCRIPTION("Amlogic Meson Reset Controller driver");

MODULE_AUTHOR("Neil Armstrong <narmstrong@baylibre.com>");

MODULE_LICENSE("Dual BSD/GPL");

drivers/reset/reset-socfpga.c

+9 −2
Original line number Diff line number Diff line
@@ -44,7 +44,7 @@ static int a10_reset_init(struct device_node *np) 
	data->membase = ioremap(res.start, size);

	if (!data->membase) {

		ret = -ENOMEM;

		goto err_alloc;

		goto release_region;

	}



	if (of_property_read_u32(np, "altr,modrst-offset", &reg_offset))
@@ -59,7 +59,14 @@ static int a10_reset_init(struct device_node *np) 
	data->rcdev.of_node = np;

	data->status_active_low = true;



	return reset_controller_register(&data->rcdev);

	ret = reset_controller_register(&data->rcdev);

	if (ret)

		pr_err("unable to register device\n");



	return ret;



release_region:

	release_mem_region(res.start, size);



err_alloc:

	kfree(data);

drivers/reset/reset-ti-syscon.c

+2 −2
Original line number Diff line number Diff line
@@ -89,7 +89,7 @@ static int ti_syscon_reset_assert(struct reset_controller_dev *rcdev, 
	mask = BIT(control->assert_bit);

	value = (control->flags & ASSERT_SET) ? mask : 0x0;



	return regmap_update_bits(data->regmap, control->assert_offset, mask, value);

	return regmap_write_bits(data->regmap, control->assert_offset, mask, value);

}



/**
@@ -120,7 +120,7 @@ static int ti_syscon_reset_deassert(struct reset_controller_dev *rcdev, 
	mask = BIT(control->deassert_bit);

	value = (control->flags & DEASSERT_SET) ? mask : 0x0;



	return regmap_update_bits(data->regmap, control->deassert_offset, mask, value);

	return regmap_write_bits(data->regmap, control->deassert_offset, mask, value);

}



/**

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