[PATCH V4 6/8] i3c: master: svc: add runtime pm support

Clark Wang
2021-08-09T06:36:37Z

Add runtime pm support to dynamically manage the clock.

Signed-off-by: Clark Wang <xiaoning.wang@nxp.com>
Reviewed-by: Jun Li <jun.li@nxp.com>
---
V4:
- error path emit_stop only used in svc_i3c_master_do_daa() for one time, so
remove it. Or it needs another goto command at the end of the function to
skip it and to go to rpm_out.
V3:
- restore the error path of probe function
- enable runtime pm just before i3c module reset
V2: New patch in V2.
---
drivers/i3c/master/svc-i3c-master.c | 154 ++++++++++++++++++++++++----
1 file changed, 135 insertions(+), 19 deletions(-)

diff --git a/drivers/i3c/master/svc-i3c-master.c b/drivers/i3c/master/svc-i3c-master.c
index 2a96b217cc78..5939e0936697 100644
--- a/drivers/i3c/master/svc-i3c-master.c
+++ b/drivers/i3c/master/svc-i3c-master.c
@@ -17,7 +17,9 @@
#include <linux/list.h>
#include <linux/module.h>
#include <linux/of.h>
+#include <linux/pinctrl/consumer.h>
#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>

/* Master Mode Registers */
#define SVC_I3C_MCONFIG 0x000
@@ -119,6 +121,7 @@
#define SVC_MDYNADDR_ADDR(x) FIELD_PREP(GENMASK(7, 1), (x))

#define SVC_I3C_MAX_DEVS 32
+#define SVC_I3C_PM_TIMEOUT_MS 1000

/* This parameter depends on the implementation and may be tuned */
#define SVC_I3C_FIFO_SIZE 16
@@ -480,10 +483,20 @@ static int svc_i3c_master_bus_init(struct i3c_master_controller *m)
u32 ppbaud, pplow, odhpp, odbaud, odstop, i2cbaud, reg;
int ret;

+ ret = pm_runtime_resume_and_get(master->dev);
+ if (ret < 0) {
+ dev_err(master->dev,
+ "<%s> cannot resume i3c bus master, err: %d\n",
+ __func__, ret);
+ return ret;
+ }
+
/* Timings derivation */
fclk_rate = clk_get_rate(master->fclk);
- if (!fclk_rate)
- return -EINVAL;
+ if (!fclk_rate) {
+ ret = -EINVAL;
+ goto rpm_out;
+ }

fclk_period_ns = DIV_ROUND_UP(1000000000, fclk_rate);

@@ -527,7 +540,7 @@ static int svc_i3c_master_bus_init(struct i3c_master_controller *m)
odstop = 1;
break;
default:
- return -EINVAL;
+ goto rpm_out;
}

reg = SVC_I3C_MCONFIG_MASTER_EN |
@@ -545,7 +558,7 @@ static int svc_i3c_master_bus_init(struct i3c_master_controller *m)
/* Master core's registration */
ret = i3c_master_get_free_addr(m, 0);
if (ret < 0)
- return ret;
+ goto rpm_out;

info.dyn_addr = ret;

@@ -554,21 +567,35 @@ static int svc_i3c_master_bus_init(struct i3c_master_controller *m)

ret = i3c_master_set_info(&master->base, &info);
if (ret)
- return ret;
+ goto rpm_out;

svc_i3c_master_enable_interrupts(master, SVC_I3C_MINT_SLVSTART);

- return 0;
+rpm_out:
+ pm_runtime_mark_last_busy(master->dev);
+ pm_runtime_put_autosuspend(master->dev);
+
+ return ret;
}

static void svc_i3c_master_bus_cleanup(struct i3c_master_controller *m)
{
struct svc_i3c_master *master = to_svc_i3c_master(m);
+ int ret;
+
+ ret = pm_runtime_resume_and_get(master->dev);
+ if (ret < 0) {
+ dev_err(master->dev, "<%s> Cannot get runtime PM.\n", __func__);
+ return;
+ }

svc_i3c_master_disable_interrupts(master);

/* Disable master */
writel(0, master->regs + SVC_I3C_MCONFIG);
+
+ pm_runtime_mark_last_busy(master->dev);
+ pm_runtime_put_autosuspend(master->dev);
}

static int svc_i3c_master_reserve_slot(struct svc_i3c_master *master)
@@ -867,31 +894,36 @@ static int svc_i3c_master_do_daa(struct i3c_master_controller *m)
unsigned int dev_nb;
int ret, i;

+ ret = pm_runtime_resume_and_get(master->dev);
+ if (ret < 0) {
+ dev_err(master->dev, "<%s> Cannot get runtime PM.\n", __func__);
+ return ret;
+ }
+
spin_lock_irqsave(&master->xferqueue.lock, flags);
ret = svc_i3c_master_do_daa_locked(master, addrs, &dev_nb);
spin_unlock_irqrestore(&master->xferqueue.lock, flags);
- if (ret)
- goto emit_stop;
+ if (ret) {
+ svc_i3c_master_emit_stop(master);
+ svc_i3c_master_clear_merrwarn(master);
+ goto rpm_out;
+ }

/* Register all devices who participated to the core */
for (i = 0; i < dev_nb; i++) {
ret = i3c_master_add_i3c_dev_locked(m, addrs[i]);
if (ret)
- return ret;
+ goto rpm_out;
}

/* Configure IBI auto-rules */
ret = svc_i3c_update_ibirules(master);
- if (ret) {
+ if (ret)
dev_err(master->dev, "Cannot handle such a list of devices");
- return ret;
- }

- return 0;
-
-emit_stop:
- svc_i3c_master_emit_stop(master);
- svc_i3c_master_clear_merrwarn(master);
+rpm_out:
+ pm_runtime_mark_last_busy(master->dev);
+ pm_runtime_put_autosuspend(master->dev);

return ret;
}
@@ -1058,6 +1090,12 @@ static void svc_i3c_master_start_xfer_locked(struct svc_i3c_master *master)
if (!xfer)
return;

+ ret = pm_runtime_resume_and_get(master->dev);
+ if (ret < 0) {
+ dev_err(master->dev, "<%s> Cannot get runtime PM.\n", __func__);
+ return;
+ }
+
svc_i3c_master_clear_merrwarn(master);
svc_i3c_master_flush_fifo(master);

@@ -1072,6 +1110,9 @@ static void svc_i3c_master_start_xfer_locked(struct svc_i3c_master *master)
break;
}

+ pm_runtime_mark_last_busy(master->dev);
+ pm_runtime_put_autosuspend(master->dev);
+
xfer->ret = ret;
complete(&xfer->comp);

@@ -1348,6 +1389,14 @@ static void svc_i3c_master_free_ibi(struct i3c_dev_desc *dev)
static int svc_i3c_master_enable_ibi(struct i3c_dev_desc *dev)
{
struct i3c_master_controller *m = i3c_dev_get_master(dev);
+ struct svc_i3c_master *master = to_svc_i3c_master(m);
+ int ret;
+
+ ret = pm_runtime_resume_and_get(master->dev);
+ if (ret < 0) {
+ dev_err(master->dev, "<%s> Cannot get runtime PM.\n", __func__);
+ return ret;
+ }

return i3c_master_enec_locked(m, dev->info.dyn_addr, I3C_CCC_EVENT_SIR);
}
@@ -1355,8 +1404,15 @@ static int svc_i3c_master_enable_ibi(struct i3c_dev_desc *dev)
static int svc_i3c_master_disable_ibi(struct i3c_dev_desc *dev)
{
struct i3c_master_controller *m = i3c_dev_get_master(dev);
+ struct svc_i3c_master *master = to_svc_i3c_master(m);
+ int ret;

- return i3c_master_disec_locked(m, dev->info.dyn_addr, I3C_CCC_EVENT_SIR);
+ ret = i3c_master_disec_locked(m, dev->info.dyn_addr, I3C_CCC_EVENT_SIR);
+
+ pm_runtime_mark_last_busy(master->dev);
+ pm_runtime_put_autosuspend(master->dev);
+
+ return ret;
}

static void svc_i3c_master_recycle_ibi_slot(struct i3c_dev_desc *dev,
@@ -1455,16 +1511,31 @@ static int svc_i3c_master_probe(struct platform_device *pdev)

platform_set_drvdata(pdev, master);

+ pm_runtime_set_autosuspend_delay(&pdev->dev, SVC_I3C_PM_TIMEOUT_MS);
+ pm_runtime_use_autosuspend(&pdev->dev);
+ pm_runtime_get_noresume(&pdev->dev);
+ pm_runtime_set_active(&pdev->dev);
+ pm_runtime_enable(&pdev->dev);
+
svc_i3c_master_reset(master);

/* Register the master */
ret = i3c_master_register(&master->base, &pdev->dev,
&svc_i3c_master_ops, false);
if (ret)
- goto err_disable_sclk;
+ goto rpm_disable;
+
+ pm_runtime_mark_last_busy(&pdev->dev);
+ pm_runtime_put_autosuspend(&pdev->dev);

return 0;

+rpm_disable:
+ pm_runtime_dont_use_autosuspend(&pdev->dev);
+ pm_runtime_put_noidle(&pdev->dev);
+ pm_runtime_set_suspended(&pdev->dev);
+ pm_runtime_disable(&pdev->dev);
+
err_disable_sclk:
clk_disable_unprepare(master->sclk);

@@ -1486,13 +1557,57 @@ static int svc_i3c_master_remove(struct platform_device *pdev)
if (ret)
return ret;

+ pm_runtime_dont_use_autosuspend(&pdev->dev);
+ pm_runtime_disable(&pdev->dev);
+
+ return 0;
+}
+
+static int __maybe_unused svc_i3c_runtime_suspend(struct device *dev)
+{
+ struct svc_i3c_master *master = dev_get_drvdata(dev);
+
clk_disable_unprepare(master->pclk);
clk_disable_unprepare(master->fclk);
clk_disable_unprepare(master->sclk);
+ pinctrl_pm_select_sleep_state(dev);

return 0;
}

+static int __maybe_unused svc_i3c_runtime_resume(struct device *dev)
+{
+ struct svc_i3c_master *master = dev_get_drvdata(dev);
+ int ret = 0;
+
+ pinctrl_pm_select_default_state(dev);
+ ret = clk_prepare_enable(master->pclk);
+ if (ret)
+ return ret;
+
+ ret = clk_prepare_enable(master->fclk);
+ if (ret) {
+ clk_disable_unprepare(master->pclk);
+ return ret;
+ }
+
+ ret = clk_prepare_enable(master->sclk);
+ if (ret) {
+ clk_disable_unprepare(master->pclk);
+ clk_disable_unprepare(master->fclk);
+ return ret;
+ }
+
+ return ret;
+}
+
+static const struct dev_pm_ops svc_i3c_pm_ops = {
+ SET_NOIRQ_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
+ pm_runtime_force_resume)
+ SET_RUNTIME_PM_OPS(svc_i3c_runtime_suspend,
+ svc_i3c_runtime_resume, NULL)
+};
+
static const struct of_device_id svc_i3c_master_of_match_tbl[] = {
{ .compatible = "silvaco,i3c-master" },
{ /* sentinel */ },
@@ -1504,6 +1619,7 @@ static struct platform_driver svc_i3c_master = {
.driver = {
.name = "silvaco-i3c-master",
.of_match_table = svc_i3c_master_of_match_tbl,
+ .pm = &svc_i3c_pm_ops,
},
};
module_platform_driver(svc_i3c_master);
--
2.25.1