reset: starfive: Add JH7100 audio reset driver
authorEmil Renner Berthing <kernel@esmil.dk>
Sat, 20 Nov 2021 18:30:49 +0000 (19:30 +0100)
committerŁukasz Stelmach <l.stelmach@samsung.com>
Thu, 9 Feb 2023 18:32:38 +0000 (19:32 +0100)
The audio resets are almost identical to the system resets, there are
just fewer of them. So factor out and export a generic probe function,
so most of the reset controller implementation can be shared.

Signed-off-by: Emil Renner Berthing <kernel@esmil.dk>
MAINTAINERS
drivers/reset/starfive/Kconfig
drivers/reset/starfive/Makefile
drivers/reset/starfive/reset-starfive-jh7100-audio.c [new file with mode: 0644]
drivers/reset/starfive/reset-starfive-jh7100.c
drivers/reset/starfive/reset-starfive-jh7100.h [new file with mode: 0644]

index 554be95..7598f96 100644 (file)
@@ -19650,12 +19650,12 @@ F:    Documentation/devicetree/bindings/pinctrl/starfive,jh7100-pinctrl.yaml
 F:     drivers/pinctrl/starfive/
 F:     include/dt-bindings/pinctrl/pinctrl-starfive-jh7100.h
 
-STARFIVE JH7100 RESET CONTROLLER DRIVER
+STARFIVE JH7100 RESET CONTROLLER DRIVERS
 M:     Emil Renner Berthing <kernel@esmil.dk>
 S:     Maintained
-F:     Documentation/devicetree/bindings/reset/starfive,jh7100-reset.yaml
-F:     drivers/reset/starfive/reset-starfive-jh7100.c
-F:     include/dt-bindings/reset/starfive-jh7100.h
+F:     Documentation/devicetree/bindings/reset/starfive,jh7100-*.yaml
+F:     drivers/reset/starfive/reset-starfive-jh7100*
+F:     include/dt-bindings/reset/starfive-jh7100*.h
 
 STATIC BRANCH/CALL
 M:     Peter Zijlstra <peterz@infradead.org>
index cddebdb..5f88d37 100644 (file)
@@ -6,3 +6,10 @@ config RESET_STARFIVE_JH7100
        default SOC_STARFIVE
        help
          This enables the reset controller driver for the StarFive JH7100 SoC.
+
+config RESET_STARFIVE_JH7100_AUDIO
+       tristate "StarFive JH7100 Audio Reset Driver"
+       depends on RESET_STARFIVE_JH7100
+       default m if SOC_STARFIVE
+       help
+         This enables the audio reset driver for the StarFive JH7100 SoC.
index 670d049..d3a55a7 100644 (file)
@@ -1,2 +1,3 @@
 # SPDX-License-Identifier: GPL-2.0
 obj-$(CONFIG_RESET_STARFIVE_JH7100)            += reset-starfive-jh7100.o
+obj-$(CONFIG_RESET_STARFIVE_JH7100_AUDIO)      += reset-starfive-jh7100-audio.o
diff --git a/drivers/reset/starfive/reset-starfive-jh7100-audio.c b/drivers/reset/starfive/reset-starfive-jh7100-audio.c
new file mode 100644 (file)
index 0000000..bae8f8c
--- /dev/null
@@ -0,0 +1,58 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Audio reset driver for the StarFive JH7100 SoC
+ *
+ * Copyright (C) 2021 Emil Renner Berthing <kernel@esmil.dk>
+ */
+
+#include <linux/mod_devicetable.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/reset-controller.h>
+
+#include <dt-bindings/reset/starfive-jh7100-audio.h>
+
+#include "reset-starfive-jh7100.h"
+
+/* register offsets */
+#define JH7100_AUDRST_ASSERT0  0x00
+#define JH7100_AUDRST_STATUS0  0x04
+
+/*
+ * Writing a 1 to the n'th bit of the ASSERT register asserts
+ * line n, and writing a 0 deasserts the same line.
+ * Most reset lines have their status inverted so a 0 bit in the STATUS
+ * register means the line is asserted and a 1 means it's deasserted. A few
+ * lines don't though, so store the expected value of the status registers when
+ * all lines are asserted.
+ */
+static const u32 jh7100_audrst_asserted[1] = {
+       BIT(JH7100_AUDRST_USB_AXI) |
+       BIT(JH7100_AUDRST_USB_PWRUP_RST_N) |
+       BIT(JH7100_AUDRST_USB_PONRST)
+};
+
+static int jh7100_audrst_probe(struct platform_device *pdev)
+{
+       return reset_starfive_jh7100_generic_probe(pdev, jh7100_audrst_asserted,
+                                                  JH7100_AUDRST_STATUS0, JH7100_AUDRSTN_END);
+}
+
+static const struct of_device_id jh7100_audrst_dt_ids[] = {
+       { .compatible = "starfive,jh7100-audrst" },
+       { /* sentinel */ }
+};
+MODULE_DEVICE_TABLE(of, jh7100_audrst_dt_ids);
+
+static struct platform_driver jh7100_audrst_driver = {
+       .probe = jh7100_audrst_probe,
+       .driver = {
+               .name = "jh7100-reset-audio",
+               .of_match_table = jh7100_audrst_dt_ids,
+       },
+};
+module_platform_driver(jh7100_audrst_driver);
+
+MODULE_AUTHOR("Emil Renner Berthing");
+MODULE_DESCRIPTION("StarFive JH7100 audio reset driver");
+MODULE_LICENSE("GPL");
index 7563d31..8e87339 100644 (file)
@@ -16,6 +16,8 @@
 
 #include <dt-bindings/reset/starfive-jh7100.h>
 
+#include "reset-starfive-jh7100.h"
+
 /* register offsets */
 #define JH7100_RESET_ASSERT0   0x00
 #define JH7100_RESET_ASSERT1   0x04
@@ -52,7 +54,9 @@ struct jh7100_reset {
        struct reset_controller_dev rcdev;
        /* protect registers against concurrent read-modify-write */
        spinlock_t lock;
-       void __iomem *base;
+       void __iomem *assert;
+       void __iomem *status;
+       const u32 *asserted;
 };
 
 static inline struct jh7100_reset *
@@ -67,9 +71,9 @@ static int jh7100_reset_update(struct reset_controller_dev *rcdev,
        struct jh7100_reset *data = jh7100_reset_from(rcdev);
        unsigned long offset = id / 32;
        u32 mask = BIT(id % 32);
-       void __iomem *reg_assert = data->base + JH7100_RESET_ASSERT0 + offset * sizeof(u32);
-       void __iomem *reg_status = data->base + JH7100_RESET_STATUS0 + offset * sizeof(u32);
-       u32 done = jh7100_reset_asserted[offset] & mask;
+       void __iomem *reg_assert = data->assert + offset * sizeof(u32);
+       void __iomem *reg_status = data->status + offset * sizeof(u32);
+       u32 done = data->asserted[offset] & mask;
        u32 value;
        unsigned long flags;
        int ret;
@@ -123,10 +127,10 @@ static int jh7100_reset_status(struct reset_controller_dev *rcdev,
        struct jh7100_reset *data = jh7100_reset_from(rcdev);
        unsigned long offset = id / 32;
        u32 mask = BIT(id % 32);
-       void __iomem *reg_status = data->base + JH7100_RESET_STATUS0 + offset * sizeof(u32);
+       void __iomem *reg_status = data->status + offset * sizeof(u32);
        u32 value = readl(reg_status);
 
-       return !((value ^ jh7100_reset_asserted[offset]) & mask);
+       return !((value ^ data->asserted[offset]) & mask);
 }
 
 static const struct reset_control_ops jh7100_reset_ops = {
@@ -136,7 +140,8 @@ static const struct reset_control_ops jh7100_reset_ops = {
        .status         = jh7100_reset_status,
 };
 
-static int __init jh7100_reset_probe(struct platform_device *pdev)
+int reset_starfive_jh7100_generic_probe(struct platform_device *pdev, const u32 *asserted,
+                                       unsigned int status_offset, unsigned int nr_resets)
 {
        struct jh7100_reset *data;
 
@@ -144,19 +149,29 @@ static int __init jh7100_reset_probe(struct platform_device *pdev)
        if (!data)
                return -ENOMEM;
 
-       data->base = devm_platform_ioremap_resource(pdev, 0);
-       if (IS_ERR(data->base))
-               return PTR_ERR(data->base);
+       data->assert = devm_platform_ioremap_resource(pdev, 0);
+       if (IS_ERR(data->assert))
+               return PTR_ERR(data->assert);
 
        data->rcdev.ops = &jh7100_reset_ops;
        data->rcdev.owner = THIS_MODULE;
-       data->rcdev.nr_resets = JH7100_RSTN_END;
+       data->rcdev.nr_resets = nr_resets;
        data->rcdev.dev = &pdev->dev;
        data->rcdev.of_node = pdev->dev.of_node;
+
        spin_lock_init(&data->lock);
+       data->status = data->assert + status_offset;
+       data->asserted = asserted;
 
        return devm_reset_controller_register(&pdev->dev, &data->rcdev);
 }
+EXPORT_SYMBOL_GPL(reset_starfive_jh7100_generic_probe);
+
+static int __init jh7100_reset_probe(struct platform_device *pdev)
+{
+       return reset_starfive_jh7100_generic_probe(pdev, jh7100_reset_asserted,
+                                                  JH7100_RESET_STATUS0, JH7100_RSTN_END);
+}
 
 static const struct of_device_id jh7100_reset_dt_ids[] = {
        { .compatible = "starfive,jh7100-reset" },
diff --git a/drivers/reset/starfive/reset-starfive-jh7100.h b/drivers/reset/starfive/reset-starfive-jh7100.h
new file mode 100644 (file)
index 0000000..ee8f3e3
--- /dev/null
@@ -0,0 +1,16 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Copyright (C) 2021 Emil Renner Berthing <kernel@esmil.dk>
+ */
+
+#ifndef _RESET_STARFIVE_JH7100_H_
+#define _RESET_STARFIVE_JH7100_H_
+
+#include <linux/platform_device.h>
+
+int reset_starfive_jh7100_generic_probe(struct platform_device *pdev,
+                                       const u32 *asserted,
+                                       unsigned int status_offset,
+                                       unsigned int nr_resets);
+
+#endif