[RFC 4/4] input: misc: Add Gateworks System Controller support

Tim Harvey
2018-02-28T01:21:14Z

Add support for dispatching Linux Input events for the various interrupts
the Gateworks System Controller provides.

Signed-off-by: Tim Harvey <tharvey@gateworks.com>
---
drivers/input/misc/Kconfig | 6 ++
drivers/input/misc/Makefile | 1 +
drivers/input/misc/gsc-input.c | 196 +++++++++++++++++++++++++++++++++++++++++
3 files changed, 203 insertions(+)
create mode 100644 drivers/input/misc/gsc-input.c

diff --git a/drivers/input/misc/Kconfig b/drivers/input/misc/Kconfig
index 9f082a3..3d18a0e 100644
--- a/drivers/input/misc/Kconfig
+++ b/drivers/input/misc/Kconfig
@@ -117,6 +117,12 @@ config INPUT_E3X0_BUTTON
To compile this driver as a module, choose M here: the
module will be called e3x0_button.

+config INPUT_GSC
+ tristate "Gateworks System Controller input support"
+ depends on MFD_GSC
+ help
+ Say Y here if you want Gateworks System Controller input support.
+
config INPUT_PCSPKR
tristate "PC Speaker support"
depends on PCSPKR_PLATFORM
diff --git a/drivers/input/misc/Makefile b/drivers/input/misc/Makefile
index 4b6118d..969debe 100644
--- a/drivers/input/misc/Makefile
+++ b/drivers/input/misc/Makefile
@@ -38,6 +38,7 @@ obj-$(CONFIG_INPUT_GP2A) += gp2ap002a00f.o
obj-$(CONFIG_INPUT_GPIO_BEEPER) += gpio-beeper.o
obj-$(CONFIG_INPUT_GPIO_TILT_POLLED) += gpio_tilt_polled.o
obj-$(CONFIG_INPUT_GPIO_DECODER) += gpio_decoder.o
+obj-$(CONFIG_INPUT_GSC) += gsc-input.o
obj-$(CONFIG_INPUT_HISI_POWERKEY) += hisi_powerkey.o
obj-$(CONFIG_HP_SDC_RTC) += hp_sdc_rtc.o
obj-$(CONFIG_INPUT_IMS_PCU) += ims-pcu.o
diff --git a/drivers/input/misc/gsc-input.c b/drivers/input/misc/gsc-input.c
new file mode 100644
index 0000000..7cf217c
--- /dev/null
+++ b/drivers/input/misc/gsc-input.c
@@ -0,0 +1,196 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ * Copyright (C) 2018 Gateworks Corporation
+ */
+#define DEBUG
+
+#include <linux/input.h>
+#include <linux/interrupt.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+
+#include <linux/mfd/gsc.h>
+
+struct gsc_irq {
+ unsigned int irq;
+ const char *name;
+ unsigned int virq;
+};
+
+static struct gsc_irq gsc_irqs[] = {
+ { GSC_IRQ_PB, "button" },
+ { GSC_IRQ_KEY_ERASED, "key-erased" },
+ { GSC_IRQ_EEPROM_WP, "eeprom-wp" },
+ { GSC_IRQ_TAMPER, "tamper" },
+ { GSC_IRQ_SWITCH_HOLD, "button-held" },
+};
+
+struct gsc_input_info {
+ struct device *dev;
+ struct gsc_dev *gsc;
+ struct input_dev *input;
+
+ int irq;
+ struct work_struct irq_work;
+ struct mutex mutex;
+};
+
+static void gsc_input_irq_work(struct work_struct *work)
+{
+ struct gsc_input_info *info = container_of(work, struct gsc_input_info,
+ irq_work);
+ struct gsc_dev *gsc = info->gsc;
+ int i, ret = 0;
+ int key, sts;
+ struct gsc_irq *gsc_irq = NULL;
+
+ dev_dbg(gsc->dev, "%s irq%d\n", __func__, info->irq);
+ mutex_lock(&info->mutex);
+
+ for (i = 0; i < ARRAY_SIZE(gsc_irqs);i++)
+ if (info->irq == gsc_irqs[i].virq)
+ gsc_irq = &gsc_irqs[i];
+ if (!gsc_irq) {
+ dev_err(info->dev, "interrupt: irq%d occurred\n", info->irq);
+ mutex_unlock(&info->mutex);
+ return;
+ }
+
+ ret = regmap_read(info->gsc->regmap, GSC_IRQ_STATUS, &sts);
+ if (ret) {
+ dev_err(info->dev, "failed to read status register\n");
+ mutex_unlock(&info->mutex);
+ return;
+ }
+
+ key = -1;
+ switch (gsc_irq->virq) {
+ case GSC_IRQ_PB:
+ key = BTN_0;
+ break;
+ case GSC_IRQ_KEY_ERASED:
+ key = BTN_1;
+ break;
+ case GSC_IRQ_EEPROM_WP:
+ key = BTN_2;
+ break;
+ case GSC_IRQ_GPIO:
+ key = BTN_3;
+ break;
+ case GSC_IRQ_TAMPER:
+ key = BTN_4;
+ break;
+ case GSC_IRQ_SWITCH_HOLD:
+ key = BTN_5;
+ break;
+ }
+
+ if (key != -1) {
+ dev_dbg(&info->input->dev, "bit%d: key=0x%03x %s\n",
+ gsc_irq->virq, key, gsc_irq->name);
+ input_report_key(info->input, key, 1);
+ input_report_key(info->input, key, 0);
+ input_sync(info->input);
+ }
+
+ mutex_unlock(&info->mutex);
+}
+
+static irqreturn_t gsc_input_irq(int irq, void *data)
+{
+ struct gsc_input_info *info = data;
+
+ dev_dbg(info->gsc->dev, "%s irq%d\n", __func__, irq);
+ info->irq = irq;
+ schedule_work(&info->irq_work);
+
+ return IRQ_HANDLED;
+}
+
+static int gsc_input_probe(struct platform_device *pdev)
+{
+ struct gsc_dev *gsc = dev_get_drvdata(pdev->dev.parent);
+ struct gsc_input_info *info;
+ struct input_dev *input;
+ int ret, i;
+
+ dev_dbg(&pdev->dev, "%s\n", __func__);
+ info = devm_kzalloc(&pdev->dev, sizeof(struct gsc_input_info),
+ GFP_KERNEL);
+ if (!info)
+ return -ENOMEM;
+ info->dev = &pdev->dev;
+ info->gsc = gsc;
+
+ /* Register input device */
+ input = devm_input_allocate_device(&pdev->dev);
+ if (!input) {
+ dev_err(&pdev->dev, "Can't allocate input device\n");
+ return -ENOMEM;
+ }
+ info->input = input;
+
+ input->name = KBUILD_MODNAME;
+ input->dev.parent = &pdev->dev;
+
+ input_set_capability(input, EV_KEY, BTN_0); /* button */
+ input_set_capability(input, EV_KEY, BTN_1); /* key erased */
+ input_set_capability(input, EV_KEY, BTN_2); /* ee wp */
+ input_set_capability(input, EV_KEY, BTN_3); /* gpio */
+ input_set_capability(input, EV_KEY, BTN_4); /* tamper */
+ input_set_capability(input, EV_KEY, BTN_5); /* button held */
+
+ ret = input_register_device(input);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "Can't register input device: %d\n", ret);
+ return ret;
+ }
+
+ platform_set_drvdata(pdev, gsc);
+ mutex_init(&info->mutex);
+ INIT_WORK(&info->irq_work, gsc_input_irq_work);
+
+ /* Support irq domain */
+ for (i = 0; i < ARRAY_SIZE(gsc_irqs); i++) {
+ struct gsc_irq *gsc_irq = &gsc_irqs[i];
+ int virq;
+
+ virq = regmap_irq_get_virq(gsc->irq_chip_data, gsc_irq->irq);
+ if (virq <= 0)
+ return -EINVAL;
+ gsc_irq->virq = virq;
+
+ ret = devm_request_threaded_irq(&pdev->dev, virq, NULL,
+ gsc_input_irq, 0,
+ gsc_irq->name, info);
+ if (ret) {
+ dev_err(&pdev->dev,
+ "failed: irq request (IRQ: %d, error: %d\n)",
+ gsc_irq->irq, ret);
+ return ret;
+ }
+ }
+
+ return 0;
+}
+
+static const struct of_device_id gsc_input_dt_ids[] = {
+ { .compatible = "gw,gsc-input", },
+ {}
+};
+
+static struct platform_driver gsc_input_driver = {
+ .driver = {
+ .name = KBUILD_MODNAME,
+ .of_match_table = gsc_input_dt_ids,
+ },
+ .probe = gsc_input_probe,
+};
+
+module_platform_driver(gsc_input_driver);
+
+MODULE_AUTHOR("Tim Harvey <tharvey@gateworks.com>");
+MODULE_DESCRIPTION("GSC input driver");
+MODULE_LICENSE("GPL v2");
--
2.7.4