[PATCH 1/3] crypto: stm32/cryp - Add power management support

From: Lionel Debieve
Date: Tue Jun 26 2018 - 08:55:46 EST


Adding pm and pm_runtime support to STM32 CRYP.

Signed-off-by: Lionel Debieve <lionel.debieve@xxxxxx>
---
drivers/crypto/stm32/stm32-cryp.c | 62 +++++++++++++++++++++++++++++++++++++++
1 file changed, 62 insertions(+)

diff --git a/drivers/crypto/stm32/stm32-cryp.c b/drivers/crypto/stm32/stm32-cryp.c
index c5d3efc..23b0b7b 100644
--- a/drivers/crypto/stm32/stm32-cryp.c
+++ b/drivers/crypto/stm32/stm32-cryp.c
@@ -11,6 +11,7 @@
#include <linux/module.h>
#include <linux/of_device.h>
#include <linux/platform_device.h>
+#include <linux/pm_runtime.h>
#include <linux/reset.h>

#include <crypto/aes.h>
@@ -105,6 +106,7 @@
#define GCM_CTR_INIT 2
#define _walked_in (cryp->in_walk.offset - cryp->in_sg->offset)
#define _walked_out (cryp->out_walk.offset - cryp->out_sg->offset)
+#define CRYP_AUTOSUSPEND_DELAY 50

struct stm32_cryp_caps {
bool swap_final;
@@ -519,6 +521,8 @@ static int stm32_cryp_hw_init(struct stm32_cryp *cryp)
int ret;
u32 cfg, hw_mode;

+ pm_runtime_get_sync(cryp->dev);
+
/* Disable interrupt */
stm32_cryp_write(cryp, CRYP_IMSCR, 0);

@@ -638,6 +642,9 @@ static void stm32_cryp_finish_req(struct stm32_cryp *cryp, int err)
free_pages((unsigned long)buf_out, pages);
}

+ pm_runtime_mark_last_busy(cryp->dev);
+ pm_runtime_put_autosuspend(cryp->dev);
+
if (is_gcm(cryp) || is_ccm(cryp)) {
crypto_finalize_aead_request(cryp->engine, cryp->areq, err);
cryp->areq = NULL;
@@ -1969,6 +1976,13 @@ static int stm32_cryp_probe(struct platform_device *pdev)
return ret;
}

+ pm_runtime_set_autosuspend_delay(dev, CRYP_AUTOSUSPEND_DELAY);
+ pm_runtime_use_autosuspend(dev);
+
+ pm_runtime_get_noresume(dev);
+ pm_runtime_set_active(dev);
+ pm_runtime_enable(dev);
+
rst = devm_reset_control_get(dev, NULL);
if (!IS_ERR(rst)) {
reset_control_assert(rst);
@@ -2008,6 +2022,8 @@ static int stm32_cryp_probe(struct platform_device *pdev)

dev_info(dev, "Initialized\n");

+ pm_runtime_put_sync(dev);
+
return 0;

err_aead_algs:
@@ -2020,6 +2036,11 @@ static int stm32_cryp_probe(struct platform_device *pdev)
list_del(&cryp->list);
spin_unlock(&cryp_list.lock);

+ pm_runtime_disable(dev);
+ pm_runtime_put_noidle(dev);
+ pm_runtime_disable(dev);
+ pm_runtime_put_noidle(dev);
+
clk_disable_unprepare(cryp->clk);

return ret;
@@ -2028,10 +2049,15 @@ static int stm32_cryp_probe(struct platform_device *pdev)
static int stm32_cryp_remove(struct platform_device *pdev)
{
struct stm32_cryp *cryp = platform_get_drvdata(pdev);
+ int ret;

if (!cryp)
return -ENODEV;

+ ret = pm_runtime_get_sync(cryp->dev);
+ if (ret < 0)
+ return ret;
+
crypto_unregister_aeads(aead_algs, ARRAY_SIZE(aead_algs));
crypto_unregister_algs(crypto_algs, ARRAY_SIZE(crypto_algs));

@@ -2041,16 +2067,52 @@ static int stm32_cryp_remove(struct platform_device *pdev)
list_del(&cryp->list);
spin_unlock(&cryp_list.lock);

+ pm_runtime_disable(cryp->dev);
+ pm_runtime_put_noidle(cryp->dev);
+
+ clk_disable_unprepare(cryp->clk);
+
+ return 0;
+}
+
+#ifdef CONFIG_PM
+static int stm32_cryp_runtime_suspend(struct device *dev)
+{
+ struct stm32_cryp *cryp = dev_get_drvdata(dev);
+
clk_disable_unprepare(cryp->clk);

return 0;
}

+static int stm32_cryp_runtime_resume(struct device *dev)
+{
+ struct stm32_cryp *cryp = dev_get_drvdata(dev);
+ int ret;
+
+ ret = clk_prepare_enable(cryp->clk);
+ if (ret) {
+ dev_err(cryp->dev, "Failed to prepare_enable clock\n");
+ return ret;
+ }
+
+ return 0;
+}
+#endif
+
+static const struct dev_pm_ops stm32_cryp_pm_ops = {
+ SET_SYSTEM_SLEEP_PM_OPS(pm_runtime_force_suspend,
+ pm_runtime_force_resume)
+ SET_RUNTIME_PM_OPS(stm32_cryp_runtime_suspend,
+ stm32_cryp_runtime_resume, NULL)
+};
+
static struct platform_driver stm32_cryp_driver = {
.probe = stm32_cryp_probe,
.remove = stm32_cryp_remove,
.driver = {
.name = DRIVER_NAME,
+ .pm = &stm32_cryp_pm_ops,
.of_match_table = stm32_dt_ids,
},
};
--
2.7.4