crypto: sunxi-ss - Add optional reset control support

On sun6i and later platforms, the reset control is split out of the
clock gates. Add support for an optional reset control.

Signed-off-by: Chen-Yu Tsai <wens@csie.org>
Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>

diff --git a/drivers/crypto/sunxi-ss/sun4i-ss-core.c b/drivers/crypto/sunxi-ss/sun4i-ss-core.c
index 0b79b58c913b92f76bb3e35089325d39b1bcc4ec..eab6fe227fa092db9ff3284f0a09a1463926489e 100644 (file)
--- a/drivers/crypto/sunxi-ss/sun4i-ss-core.c
+++ b/drivers/crypto/sunxi-ss/sun4i-ss-core.c
@@ -22,6 +22,7 @@
 #include <linux/scatterlist.h>
 #include <linux/interrupt.h>
 #include <linux/delay.h>
+#include <linux/reset.h>
 
 #include "sun4i-ss.h"
 
@@ -253,6 +254,14 @@ static int sun4i_ss_probe(struct platform_device *pdev)
        }
        dev_dbg(&pdev->dev, "clock ahb_ss acquired\n");
 
+       ss->reset = devm_reset_control_get_optional(&pdev->dev, "ahb");
+       if (IS_ERR(ss->reset)) {
+               if (PTR_ERR(ss->reset) == -EPROBE_DEFER)
+                       return PTR_ERR(ss->reset);
+               dev_info(&pdev->dev, "no reset control found\n");
+               ss->reset = NULL;
+       }
+
        /* Enable both clocks */
        err = clk_prepare_enable(ss->busclk);
        if (err != 0) {
@@ -275,6 +284,15 @@ static int sun4i_ss_probe(struct platform_device *pdev)
                goto error_clk;
        }
 
+       /* Deassert reset if we have a reset control */
+       if (ss->reset) {
+               err = reset_control_deassert(ss->reset);
+               if (err) {
+                       dev_err(&pdev->dev, "Cannot deassert reset control\n");
+                       goto error_clk;
+               }
+       }
+
        /*
         * The only impact on clocks below requirement are bad performance,
         * so do not print "errors"
@@ -352,6 +370,8 @@ error_alg:
                        break;
                }
        }
+       if (ss->reset)
+               reset_control_assert(ss->reset);
 error_clk:
        clk_disable_unprepare(ss->ssclk);
 error_ssclk:
@@ -376,6 +396,8 @@ static int sun4i_ss_remove(struct platform_device *pdev)
        }
 
        writel(0, ss->base + SS_CTL);
+       if (ss->reset)
+               reset_control_assert(ss->reset);
        clk_disable_unprepare(ss->busclk);
        clk_disable_unprepare(ss->ssclk);
        return 0;

diff --git a/drivers/crypto/sunxi-ss/sun4i-ss.h b/drivers/crypto/sunxi-ss/sun4i-ss.h
index db18b2554e6f02ae629c1c7eeedda2a91eca91b2..8e9c05f6e4d4baa59aae21b1eec78f6c666faf56 100644 (file)
--- a/drivers/crypto/sunxi-ss/sun4i-ss.h
+++ b/drivers/crypto/sunxi-ss/sun4i-ss.h
@@ -18,6 +18,7 @@
 #include <linux/module.h>
 #include <linux/of.h>
 #include <linux/platform_device.h>
+#include <linux/reset.h>
 #include <crypto/scatterwalk.h>
 #include <linux/scatterlist.h>
 #include <linux/interrupt.h>
@@ -129,6 +130,7 @@ struct sun4i_ss_ctx {
        int irq;
        struct clk *busclk;
        struct clk *ssclk;
+       struct reset_control *reset;
        struct device *dev;
        struct resource *res;
        spinlock_t slock; /* control the use of the device */