Commit 9225bcde authored by Nishanth Menon's avatar Nishanth Menon
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firmware: ti_sci: Use system_state to determine polling 



Commit b9e8a7d9 ("firmware: ti_sci: Switch transport to polled
mode during system suspend") aims to resolve issues with tisci
operations during system suspend operation. However, the system may
enter a no_irq stage in various other usage modes, including power-off
and restart. To determine if polling mode is appropriate, use the
system_state instead.

While at this, drop the unused is_suspending state variable and
related helpers.

Fixes: b9e8a7d9 ("firmware: ti_sci: Switch transport to polled mode during system suspend")
Reported-by: default avatarFrancesco Dolcini <francesco@dolcini.it>
Reported-by: default avatarWadim Egorov <w.egorov@phytec.de>
Tested-by: Francesco Dolcini <francesco.dolcini@toradex.com> # Toradex Verdin AM62
Link: https://lore.kernel.org/r/20230620130329.4120443-1-nm@ti.com
Closes: https://lore.kernel.org/all/ZGeHMjlnob2GFyHF@francesco-nb.int.toradex.com/


Signed-off-by: default avatarNishanth Menon <nm@ti.com>
parent 06c2afb8

drivers/firmware/ti_sci.c

+2 −34
Original line number Diff line number Diff line
@@ -97,7 +97,6 @@ struct ti_sci_desc { 
 * @node:	list head

 * @host_id:	Host ID

 * @users:	Number of users of this instance

 * @is_suspending: Flag set to indicate in suspend path.

 */

struct ti_sci_info {

	struct device *dev;
@@ -116,7 +115,6 @@ struct ti_sci_info { 
	u8 host_id;

	/* protected by ti_sci_list_mutex */

	int users;

	bool is_suspending;

};



#define cl_to_ti_sci_info(c)	container_of(c, struct ti_sci_info, cl)
@@ -418,14 +416,14 @@ static inline int ti_sci_do_xfer(struct ti_sci_info *info, 


	ret = 0;



	if (!info->is_suspending) {

	if (system_state <= SYSTEM_RUNNING) {

		/* And we wait for the response. */

		timeout = msecs_to_jiffies(info->desc->max_rx_timeout_ms);

		if (!wait_for_completion_timeout(&xfer->done, timeout))

			ret = -ETIMEDOUT;

	} else {

		/*

		 * If we are suspending, we cannot use wait_for_completion_timeout

		 * If we are !running, we cannot use wait_for_completion_timeout

		 * during noirq phase, so we must manually poll the completion.

		 */

		ret = read_poll_timeout_atomic(try_wait_for_completion, done_state,
@@ -3281,35 +3279,6 @@ static int tisci_reboot_handler(struct notifier_block *nb, unsigned long mode, 
	return NOTIFY_BAD;

}



static void ti_sci_set_is_suspending(struct ti_sci_info *info, bool is_suspending)

{

	info->is_suspending = is_suspending;

}



static int ti_sci_suspend(struct device *dev)

{

	struct ti_sci_info *info = dev_get_drvdata(dev);

	/*

	 * We must switch operation to polled mode now as drivers and the genpd

	 * layer may make late TI SCI calls to change clock and device states

	 * from the noirq phase of suspend.

	 */

	ti_sci_set_is_suspending(info, true);



	return 0;

}



static int ti_sci_resume(struct device *dev)

{

	struct ti_sci_info *info = dev_get_drvdata(dev);



	ti_sci_set_is_suspending(info, false);



	return 0;

}



static DEFINE_SIMPLE_DEV_PM_OPS(ti_sci_pm_ops, ti_sci_suspend, ti_sci_resume);



/* Description for K2G */

static const struct ti_sci_desc ti_sci_pmmc_k2g_desc = {

	.default_host_id = 2,
@@ -3516,7 +3485,6 @@ static struct platform_driver ti_sci_driver = { 
	.driver = {

		   .name = "ti-sci",

		   .of_match_table = of_match_ptr(ti_sci_of_match),

		   .pm = &ti_sci_pm_ops,

	},

};

module_platform_driver(ti_sci_driver);