summaryrefslogtreecommitdiffstats
path: root/drivers/base/pinctrl.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/base/pinctrl.c')
-rw-r--r--drivers/base/pinctrl.c105
1 files changed, 105 insertions, 0 deletions
diff --git a/drivers/base/pinctrl.c b/drivers/base/pinctrl.c
new file mode 100644
index 000000000..c22864458
--- /dev/null
+++ b/drivers/base/pinctrl.c
@@ -0,0 +1,105 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Driver core interface to the pinctrl subsystem.
+ *
+ * Copyright (C) 2012 ST-Ericsson SA
+ * Written on behalf of Linaro for ST-Ericsson
+ * Based on bits of regulator core, gpio core and clk core
+ *
+ * Author: Linus Walleij <linus.walleij@linaro.org>
+ */
+
+#include <linux/device.h>
+#include <linux/pinctrl/devinfo.h>
+#include <linux/pinctrl/consumer.h>
+#include <linux/slab.h>
+
+/**
+ * pinctrl_bind_pins() - called by the device core before probe
+ * @dev: the device that is just about to probe
+ */
+int pinctrl_bind_pins(struct device *dev)
+{
+ int ret;
+
+ if (dev->of_node_reused)
+ return 0;
+
+ dev->pins = devm_kzalloc(dev, sizeof(*(dev->pins)), GFP_KERNEL);
+ if (!dev->pins)
+ return -ENOMEM;
+
+ dev->pins->p = devm_pinctrl_get(dev);
+ if (IS_ERR(dev->pins->p)) {
+ dev_dbg(dev, "no pinctrl handle\n");
+ ret = PTR_ERR(dev->pins->p);
+ goto cleanup_alloc;
+ }
+
+ dev->pins->default_state = pinctrl_lookup_state(dev->pins->p,
+ PINCTRL_STATE_DEFAULT);
+ if (IS_ERR(dev->pins->default_state)) {
+ dev_dbg(dev, "no default pinctrl state\n");
+ ret = 0;
+ goto cleanup_get;
+ }
+
+ dev->pins->init_state = pinctrl_lookup_state(dev->pins->p,
+ PINCTRL_STATE_INIT);
+ if (IS_ERR(dev->pins->init_state)) {
+ /* Not supplying this state is perfectly legal */
+ dev_dbg(dev, "no init pinctrl state\n");
+
+ ret = pinctrl_select_state(dev->pins->p,
+ dev->pins->default_state);
+ } else {
+ ret = pinctrl_select_state(dev->pins->p, dev->pins->init_state);
+ }
+
+ if (ret) {
+ dev_dbg(dev, "failed to activate initial pinctrl state\n");
+ goto cleanup_get;
+ }
+
+#ifdef CONFIG_PM
+ /*
+ * If power management is enabled, we also look for the optional
+ * sleep and idle pin states, with semantics as defined in
+ * <linux/pinctrl/pinctrl-state.h>
+ */
+ dev->pins->sleep_state = pinctrl_lookup_state(dev->pins->p,
+ PINCTRL_STATE_SLEEP);
+ if (IS_ERR(dev->pins->sleep_state))
+ /* Not supplying this state is perfectly legal */
+ dev_dbg(dev, "no sleep pinctrl state\n");
+
+ dev->pins->idle_state = pinctrl_lookup_state(dev->pins->p,
+ PINCTRL_STATE_IDLE);
+ if (IS_ERR(dev->pins->idle_state))
+ /* Not supplying this state is perfectly legal */
+ dev_dbg(dev, "no idle pinctrl state\n");
+#endif
+
+ return 0;
+
+ /*
+ * If no pinctrl handle or default state was found for this device,
+ * let's explicitly free the pin container in the device, there is
+ * no point in keeping it around.
+ */
+cleanup_get:
+ devm_pinctrl_put(dev->pins->p);
+cleanup_alloc:
+ devm_kfree(dev, dev->pins);
+ dev->pins = NULL;
+
+ /* Return deferrals */
+ if (ret == -EPROBE_DEFER)
+ return ret;
+ /* Return serious errors */
+ if (ret == -EINVAL)
+ return ret;
+ /* We ignore errors like -ENOENT meaning no pinctrl state */
+
+ return 0;
+}