[PATCH v3 2/5] input: misc: introduce Atmel PTC driver

Ludovic Desroches
2017-10-20T13:31:18Z

The Atmel Peripheral Touch Controller subsystem offers built-in hardware
for capacitive touch measurement on sensors that function as buttons,
sliders and wheels.

Two files are loaded when probing the driver:
- a firmware for the Pico Power Processor that computes raw data from
the ADC front end to provide high level information as button touch or
untouch, slider position, etc.
- a configuration file that describe the topology and the parameters of
the sensors.

Signed-off-by: Ludovic Desroches <ludovic.desroches@microchip.com>
---
drivers/input/misc/Kconfig | 12 +
drivers/input/misc/Makefile | 1 +
drivers/input/misc/atmel_ptc.c | 723 +++++++++++++++++++++++++++++++++++++++++
3 files changed, 736 insertions(+)
create mode 100644 drivers/input/misc/atmel_ptc.c

diff --git a/drivers/input/misc/Kconfig b/drivers/input/misc/Kconfig
index 9f082a388388..76616b0425b5 100644
--- a/drivers/input/misc/Kconfig
+++ b/drivers/input/misc/Kconfig
@@ -96,6 +96,18 @@ config INPUT_ATMEL_CAPTOUCH
To compile this driver as a module, choose M here: the
module will be called atmel_captouch.

+config INPUT_ATMEL_PTC
+ tristate "Atmel PTC Driver"
+ depends on OF || COMPILE_TEST
+ depends on SOC_SAMA5D2
+ help
+ Say Y to enable support for the Atmel PTC Subsystem.
+
+ To compile this driver as a module, choose M here: the
+ module will be called atmel_ptc.
+ If you compile it as a built-in driver, you have to build the
+ firmware into the kernel or to use an initrd.
+
config INPUT_BMA150
tristate "BMA150/SMB380 acceleration sensor support"
depends on I2C
diff --git a/drivers/input/misc/Makefile b/drivers/input/misc/Makefile
index 03fd4262ada9..f71972adc002 100644
--- a/drivers/input/misc/Makefile
+++ b/drivers/input/misc/Makefile
@@ -18,6 +18,7 @@ obj-$(CONFIG_INPUT_ARIZONA_HAPTICS) += arizona-haptics.o
obj-$(CONFIG_INPUT_ATI_REMOTE2) += ati_remote2.o
obj-$(CONFIG_INPUT_ATLAS_BTNS) += atlas_btns.o
obj-$(CONFIG_INPUT_ATMEL_CAPTOUCH) += atmel_captouch.o
+obj-$(CONFIG_INPUT_ATMEL_PTC) += atmel_ptc.o
obj-$(CONFIG_INPUT_BFIN_ROTARY) += bfin_rotary.o
obj-$(CONFIG_INPUT_BMA150) += bma150.o
obj-$(CONFIG_INPUT_CM109) += cm109.o
diff --git a/drivers/input/misc/atmel_ptc.c b/drivers/input/misc/atmel_ptc.c
new file mode 100644
index 000000000000..612eaede6072
--- /dev/null
+++ b/drivers/input/misc/atmel_ptc.c
@@ -0,0 +1,723 @@
+/*
+ * Atmel PTC subsystem driver for SAMA5D2 devices and compatible.
+ *
+ * Copyright (C) 2017 Microchip,
+ * 2017 Ludovic Desroches <ludovic.desroches@microchip.com>
+ *
+ * This software is licensed under the terms of the GNU General Public
+ * License version 2, as published by the Free Software Foundation, and
+ * may be copied, distributed, and modified under those terms.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ */
+
+#include <linux/cdev.h>
+#include <linux/clk.h>
+#include <linux/delay.h>
+#include <linux/device.h>
+#include <linux/firmware.h>
+#include <linux/input.h>
+#include <linux/interrupt.h>
+#include <linux/io.h>
+#include <linux/module.h>
+#include <linux/of.h>
+#include <linux/platform_device.h>
+#include <linux/slab.h>
+#include <linux/types.h>
+#include <linux/uaccess.h>
+
+#define ATMEL_PTC_MAX_NODES 64
+#define ATMEL_PTC_MAX_SCROLLERS 4
+
+/* ----- PPP ----- */
+#define ATMEL_PPP_FIRMWARE_NAME "atmel_ptc.bin"
+
+#define ATMEL_PPP_CONFIG 0x20
+#define ATMEL_PPP_CTRL 0x24
+#define ATMEL_PPP_CMD 0x28
+#define ATMEL_PPP_CMD_STOP 0x1
+#define ATMEL_PPP_CMD_RESET 0x2
+#define ATMEL_PPP_CMD_RESTART 0x3
+#define ATMEL_PPP_CMD_ABORT 0x4
+#define ATMEL_PPP_CMD_RUN 0x5
+#define ATMEL_PPP_CMD_RUN_LOCKED 0x6
+#define ATMEL_PPP_CMD_RUN_OCD 0x7
+#define ATMEL_PPP_CMD_UNLOCK 0x8
+#define ATMEL_PPP_CMD_NMI 0x9
+#define ATMEL_PPP_CMD_HOST_OCD_RESUME 0xB
+#define ATMEL_PPP_ISR 0x33
+#define ATMEL_PPP_IRQ_MASK GENMASK(7, 4)
+#define ATMEL_PPP_IRQ0 BIT(4)
+#define ATMEL_PPP_IRQ1 BIT(5)
+#define ATMEL_PPP_IRQ2 BIT(6)
+#define ATMEL_PPP_IRQ3 BIT(7)
+#define ATMEL_PPP_NOTIFY_MASK GENMASK(3, 0)
+#define ATMEL_PPP_NOTIFY0 BIT(0)
+#define ATMEL_PPP_NOTIFY1 BIT(1)
+#define ATMEL_PPP_NOTIFY2 BIT(2)
+#define ATMEL_PPP_NOTIFY3 BIT(3)
+#define ATMEL_PPP_IDR 0x34
+#define ATMEL_PPP_IER 0x35
+
+#define atmel_ppp_readb(ptc, reg) readb_relaxed(ptc->ppp_regs + reg)
+#define atmel_ppp_writeb(ptc, reg, val) writeb_relaxed(val, ptc->ppp_regs + reg)
+#define atmel_ppp_readl(ptc, reg) readl_relaxed(ptc->ppp_regs + reg)
+#define atmel_ppp_writel(ptc, reg, val) writel_relaxed(val, ptc->ppp_regs + reg)
+
+/* ----- QTM ----- */
+#define ATMEL_QTM_CONF_NAME "atmel_ptc.conf"
+
+#define ATMEL_QTM_MB_OFFSET 0x4000
+#define ATMEL_QTM_MB_SIZE 0x1000
+
+#define ATMEL_QTM_MB_CMD_OFFSET 0x0
+#define ATMEL_QTM_CMD_FIRM_VERSION 8
+#define ATMEL_QTM_CMD_INIT 18
+#define ATMEL_QTM_CMD_RUN 19
+#define ATMEL_QTM_CMD_STOP 21
+#define ATMEL_QTM_CMD_SET_ACQ_MODE_TIMER 24
+#define ATMEL_QTM_MB_NODE_GROUP_CONFIG_OFFSET 0x100
+#define ATMEL_QTM_MB_SCROLLER_CONFIG_OFFSET 0x81a
+#define ATMEL_QTM_SCROLLER_TYPE_SLIDER 0x0
+#define ATMEL_QTM_SCROLLER_TYPE_WHEEL 0x1
+#define ATMEL_QTM_MB_SCROLLER_DATA_OFFSET 0x842
+#define ATMEL_QTM_MB_TOUCH_EVENTS_OFFSET 0x880
+
+#define atmel_qtm_get_scroller_config(buf, id) \
+ memcpy(buf, \
+ ptc->qtm_mb + ATMEL_QTM_MB_SCROLLER_CONFIG_OFFSET \
+ + (id) * sizeof(struct atmel_qtm_scroller_config), \
+ sizeof(struct atmel_qtm_scroller_config))
+
+#define atmel_qtm_get_scroller_data(buf, id) \
+ memcpy(buf, \
+ ptc->qtm_mb + ATMEL_QTM_MB_SCROLLER_DATA_OFFSET \
+ + (id) * sizeof(struct atmel_qtm_scroller_data), \
+ sizeof(struct atmel_qtm_scroller_data))
+
+#define get_scroller_resolution(scroller_config) \
+ (1 << (scroller_config.resol_deadband >> 4))
+
+struct atmel_qtm_cmd {
+ u16 id;
+ u16 addr;
+ u32 data;
+} __packed;
+
+struct atmel_qtm_node_group_config {
+ u16 count;
+ u8 ptc_type;
+ u8 freq_option;
+ u8 calib_option;
+ u8 unused;
+} __packed;
+
+struct atmel_qtm_scroller_config {
+ u8 type;
+ u8 unused;
+ u16 key_start;
+ u8 key_count;
+ u8 resol_deadband;
+ u8 position_hysteresis;
+ u8 unused2;
+ u16 contact_min_threshold;
+} __packed;
+
+struct atmel_qtm_scroller_data {
+ u8 status;
+ u8 right_hyst;
+ u8 left_hyst;
+ u8 unused;
+ u16 raw_position;
+ u16 position;
+ u16 contact_size;
+} __packed;
+
+struct atmel_qtm_touch_events {
+ u32 key_event_id[2];
+ u32 key_enable_state[2];
+ u32 scroller_event_id;
+ u32 scroller_event_state;
+} __packed;
+
+struct atmel_ptc {
+ void __iomem *ppp_regs;
+ void __iomem *firmware;
+ int irq;
+ u8 imr;
+ void __iomem *qtm_mb;
+ struct clk *clk_per;
+ struct clk *clk_int_osc;
+ struct clk *clk_slow;
+ struct device *dev;
+ struct completion ppp_ack;
+ unsigned int button_keycode[ATMEL_PTC_MAX_NODES];
+ struct input_dev *buttons_input;
+ struct input_dev *scroller_input[ATMEL_PTC_MAX_SCROLLERS];
+ bool buttons_registered;
+ bool scroller_registered[ATMEL_PTC_MAX_SCROLLERS];
+ u32 button_event[ATMEL_PTC_MAX_NODES / 32];
+ u32 button_state[ATMEL_PTC_MAX_NODES / 32];
+ u32 scroller_event;
+ u32 scroller_state;
+};
+
+static void atmel_ppp_irq_enable(struct atmel_ptc *ptc, u8 mask)
+{
+ ptc->imr |= mask;
+ atmel_ppp_writeb(ptc, ATMEL_PPP_IER, mask & ATMEL_PPP_IRQ_MASK);
+}
+
+static void atmel_ppp_irq_disable(struct atmel_ptc *ptc, u8 mask)
+{
+ ptc->imr &= ~mask;
+ atmel_ppp_writeb(ptc, ATMEL_PPP_IDR, mask & ATMEL_PPP_IRQ_MASK);
+}
+
+static void atmel_ppp_notify(struct atmel_ptc *ptc, u8 mask)
+{
+ if (mask & ATMEL_PPP_NOTIFY_MASK) {
+ u8 notify = atmel_ppp_readb(ptc, ATMEL_PPP_ISR)
+ | (mask & ATMEL_PPP_NOTIFY_MASK);
+
+ atmel_ppp_writeb(ptc, ATMEL_PPP_ISR, notify);
+ }
+}
+
+static void atmel_ppp_irq_pending_clr(struct atmel_ptc *ptc, u8 mask)
+{
+ if (mask & ATMEL_PPP_IRQ_MASK) {
+ u8 irq = atmel_ppp_readb(ptc, ATMEL_PPP_ISR) & ~mask;
+
+ atmel_ppp_writeb(ptc, ATMEL_PPP_ISR, irq);
+ }
+}
+
+static void atmel_ppp_cmd_send(struct atmel_ptc *ptc, u32 cmd)
+{
+ atmel_ppp_writel(ptc, ATMEL_PPP_CMD, cmd);
+}
+
+static void atmel_ppp_irq_scroller_event(struct atmel_ptc *ptc)
+{
+ int i;
+
+ if (!ptc->scroller_event)
+ return;
+
+ for (i = 0; i < ATMEL_PTC_MAX_SCROLLERS; i++) {
+ u32 mask = 1 << i;
+ struct atmel_qtm_scroller_data scroller_data;
+ struct atmel_qtm_scroller_config scroller_config;
+
+ if (!(ptc->scroller_event & mask))
+ continue;
+
+ atmel_qtm_get_scroller_data(&scroller_data, i);
+ atmel_qtm_get_scroller_config(&scroller_config, i);
+
+ if (scroller_config.type == ATMEL_QTM_SCROLLER_TYPE_WHEEL)
+ input_report_abs(ptc->scroller_input[i],
+ ABS_WHEEL, scroller_data.position);
+ else
+ input_report_abs(ptc->scroller_input[i],
+ ABS_X, scroller_data.position);
+
+ input_report_key(ptc->scroller_input[i], BTN_TOUCH,
+ scroller_data.status & 0x1);
+ input_sync(ptc->scroller_input[i]);
+ }
+}
+
+static void atmel_ppp_irq_button_event(struct atmel_ptc *ptc)
+{
+ int i, j;
+
+ for (i = 0; i < ATMEL_PTC_MAX_NODES / 32; i++) {
+ if (!ptc->button_event[i])
+ continue;
+
+ for (j = 0; j < 32; j++) {
+ u32 mask = 1 << j;
+ u32 state = ptc->button_state[i] & mask;
+ unsigned int key_id = i * 32 + j;
+
+ if (!(ptc->button_event[i] & mask))
+ continue;
+
+ input_report_key(ptc->buttons_input,
+ ptc->button_keycode[key_id], !!state);
+ input_sync(ptc->buttons_input);
+ }
+ }
+}
+
+static void atmel_ppp_irq_touch_event(struct atmel_ptc *ptc)
+{
+ atmel_ppp_irq_scroller_event(ptc);
+ atmel_ppp_irq_button_event(ptc);
+}
+
+static irqreturn_t atmel_ppp_irq_handler(int irq, void *data)
+{
+ struct atmel_ptc *ptc = data;
+ u32 isr = atmel_ppp_readb(ptc, ATMEL_PPP_ISR) & ptc->imr;
+
+ /* QTM CMD acknowledgment */
+ if (isr & ATMEL_PPP_IRQ0) {
+ atmel_ppp_irq_disable(ptc, ATMEL_PPP_IRQ0);
+ atmel_ppp_irq_pending_clr(ptc, ATMEL_PPP_IRQ0);
+ complete(&ptc->ppp_ack);
+ }
+ /* QTM touch event */
+ if (isr & ATMEL_PPP_IRQ1) {
+ struct atmel_qtm_touch_events touch_events;
+ int i;
+
+ memcpy(&touch_events,
+ ptc->qtm_mb + ATMEL_QTM_MB_TOUCH_EVENTS_OFFSET,
+ sizeof(touch_events));
+
+ for (i = 0; i < ATMEL_PTC_MAX_NODES / 32; i++) {
+ ptc->button_event[i] = touch_events.key_event_id[i];
+ ptc->button_state[i] = touch_events.key_enable_state[i];
+ }
+ ptc->scroller_event = touch_events.scroller_event_id;
+ ptc->scroller_state = touch_events.scroller_event_state;
+
+ atmel_ppp_irq_pending_clr(ptc, ATMEL_PPP_IRQ1);
+
+ atmel_ppp_irq_touch_event(ptc);
+ }
+ /* Debug event */
+ if (isr & ATMEL_PPP_IRQ2)
+ atmel_ppp_irq_pending_clr(ptc, ATMEL_PPP_IRQ2);
+
+ return IRQ_HANDLED;
+}
+
+void atmel_qtm_cmd_send(struct atmel_ptc *ptc, struct atmel_qtm_cmd *cmd)
+{
+ int i, ret;
+
+ dev_dbg(ptc->dev, "%s: cmd=0x%x, addr=0x%x, data=0x%x\n",
+ __func__, cmd->id, cmd->addr, cmd->data);
+
+ memcpy(ptc->qtm_mb, cmd, sizeof(*cmd));
+
+ /* Once command performed, we'll get an IRQ. */
+ atmel_ppp_irq_enable(ptc, ATMEL_PPP_IRQ0);
+ /* Notify PPP that we have sent a command. */
+ atmel_ppp_notify(ptc, ATMEL_PPP_NOTIFY0);
+ /* Wait for IRQ from PPP. */
+ wait_for_completion(&ptc->ppp_ack);
+
+ /*
+ * Register input devices only when QTM is started since we need some
+ * information from the QTM configuration.
+ */
+ if (cmd->id == ATMEL_QTM_CMD_RUN) {
+ if (ptc->buttons_input && !ptc->buttons_registered) {
+ ret = input_register_device(ptc->buttons_input);
+ if (ret)
+ dev_err(ptc->dev, "can't register input button device.\n");
+ else
+ ptc->buttons_registered = true;
+ }
+
+ for (i = 0; i < ATMEL_PTC_MAX_SCROLLERS; i++) {
+ struct input_dev *scroller = ptc->scroller_input[i];
+ struct atmel_qtm_scroller_config scroller_config;
+
+ if (!scroller || ptc->scroller_registered[i])
+ continue;
+
+ atmel_qtm_get_scroller_config(&scroller_config, i);
+
+ if (scroller_config.type ==
+ ATMEL_QTM_SCROLLER_TYPE_SLIDER) {
+ unsigned int max = get_scroller_resolution(scroller_config);
+
+ input_set_abs_params(scroller, 0, 0, max, 0, 0);
+ }
+ ret = input_register_device(scroller);
+ if (ret)
+ dev_err(ptc->dev, "can't register input scroller device.\n");
+ else
+ ptc->scroller_registered[i] = true;
+ }
+ }
+
+ memcpy(cmd, ptc->qtm_mb, sizeof(*cmd));
+}
+
+static inline struct atmel_ptc *kobj_to_atmel_ptc(struct kobject *kobj)
+{
+ struct device *dev = kobj_to_dev(kobj);
+
+ return dev->driver_data;
+}
+
+static ssize_t atmel_qtm_mb_read(struct file *filp, struct kobject *kobj,
+ struct bin_attribute *attr,
+ char *buf, loff_t off, size_t count)
+{
+ struct atmel_ptc *ptc = kobj_to_atmel_ptc(kobj);
+ char *qtm_mb = (char *)ptc->qtm_mb;
+
+ dev_dbg(ptc->dev, "%s: off=0x%llx, count=%zu\n", __func__, off, count);
+
+ memcpy(buf, qtm_mb + off, count);
+
+ return count;
+}
+
+static ssize_t atmel_qtm_mb_write(struct file *filp, struct kobject *kobj,
+ struct bin_attribute *attr,
+ char *buf, loff_t off, size_t count)
+{
+ struct atmel_ptc *ptc = kobj_to_atmel_ptc(kobj);
+ char *qtm_mb = (char *)ptc->qtm_mb;
+
+ dev_dbg(ptc->dev, "%s: off=0x%llx, count=%zu\n", __func__, off, count);
+
+ if (off == 0 && count == sizeof(struct atmel_qtm_cmd))
+ atmel_qtm_cmd_send(ptc, (struct atmel_qtm_cmd *)buf);
+ else
+ memcpy(qtm_mb + off, buf, count);
+
+ return count;
+}
+
+static struct bin_attribute atmel_ptc_qtm_mb_attr = {
+ .attr = {
+ .name = "qtm_mb",
+ .mode = 0644,
+ },
+ .size = ATMEL_QTM_MB_SIZE,
+ .read = atmel_qtm_mb_read,
+ .write = atmel_qtm_mb_write,
+};
+
+/*
+ * From QTM MB configuration, we can't retrieve all the information needed
+ * to setup correctly input devices: buttons key codes and slider axis are
+ * missing.
+ */
+static int atmel_ptc_of_parse(struct atmel_ptc *ptc)
+{
+ struct device_node *sensor;
+ bool first_button = true;
+
+ /* Parse sensors. */
+ for_each_child_of_node(ptc->dev->of_node, sensor) {
+ if (!strcmp(sensor->name, "button")) {
+ u32 key_id, keycode;
+ struct input_dev *buttons = ptc->buttons_input;
+
+ if (of_property_read_u32(sensor, "reg", &key_id)) {
+ dev_err(ptc->dev, "reg is missing (%s)\n",
+ sensor->full_name);
+ return -EINVAL;
+ }
+
+ if (of_property_read_u32(sensor, "linux,keycode", &keycode)) {
+ dev_err(ptc->dev, "linux,keycode is missing (%s)\n",
+ sensor->full_name);
+ return -EINVAL;
+ }
+ ptc->button_keycode[key_id] = keycode;
+
+ /* All buttons are put together in a keyboard device. */
+ if (first_button) {
+ buttons = devm_input_allocate_device(ptc->dev);
+ if (!buttons)
+ return -ENOMEM;
+ buttons->name = "atmel_ptc_buttons";
+ buttons->dev.parent = ptc->dev;
+ buttons->keycode = ptc->button_keycode;
+ buttons->keycodesize = sizeof(ptc->button_keycode[0]);
+ buttons->keycodemax = ATMEL_PTC_MAX_NODES;
+ ptc->buttons_input = buttons;
+ first_button = false;
+ }
+
+ input_set_capability(buttons, EV_KEY, keycode);
+ } else if (!strcmp(sensor->name, "slider") ||
+ !strcmp(sensor->name, "wheel")) {
+ u32 scroller_id;
+ struct input_dev *scroller;
+
+ if (of_property_read_u32(sensor, "reg", &scroller_id)) {
+ dev_err(ptc->dev, "reg is missing (%s)\n",
+ sensor->full_name);
+ return -EINVAL;
+ }
+
+ if (scroller_id > ATMEL_PTC_MAX_SCROLLERS - 1) {
+ dev_err(ptc->dev, "wrong scroller id (%s)\n",
+ sensor->full_name);
+ return -EINVAL;
+ }
+
+ scroller = devm_input_allocate_device(ptc->dev);
+ if (!scroller)
+ return -ENOMEM;
+
+ scroller->dev.parent = ptc->dev;
+ ptc->scroller_input[scroller_id] = scroller;
+
+ if (!strcmp(sensor->name, "slider")) {
+ scroller->name = "atmel_ptc_slider";
+ input_set_capability(scroller, EV_ABS, ABS_X);
+ input_set_capability(scroller, EV_KEY, BTN_TOUCH);
+ } else {
+ scroller->name = "atmel_ptc_wheel";
+ input_set_capability(scroller, EV_ABS, ABS_WHEEL);
+ input_set_capability(scroller, EV_KEY, BTN_TOUCH);
+ }
+ } else {
+ dev_err(ptc->dev, "%s is not supported\n", sensor->name);
+ return -EINVAL;
+ }
+ }
+
+ return 0;
+}
+
+static void atmel_qtm_conf_callback(const struct firmware *conf, void *context)
+{
+ struct atmel_ptc *ptc = context;
+ struct atmel_qtm_cmd qtm_cmd;
+ char *dst;
+ struct atmel_qtm_node_group_config node_group_config;
+
+ if (!conf) {
+ dev_err(ptc->dev, "cannot load QTM configuration, it has to be set manually.\n");
+ return;
+ }
+
+ atmel_ppp_irq_enable(ptc, ATMEL_PPP_IRQ1);
+ atmel_ppp_irq_disable(ptc, ATMEL_PPP_IRQ2 | ATMEL_PPP_IRQ3);
+
+ qtm_cmd.id = ATMEL_QTM_CMD_STOP;
+ atmel_qtm_cmd_send(ptc, &qtm_cmd);
+
+ /* Load QTM configuration. */
+ dst = (char *)ptc->qtm_mb + ATMEL_QTM_MB_NODE_GROUP_CONFIG_OFFSET;
+ /* memcpy doesn't work for an unknown reason. */
+ _memcpy_toio(dst, conf->data, conf->size);
+ release_firmware(conf);
+
+ if (atmel_ptc_of_parse(ptc))
+ dev_err(ptc->dev, "ptc_of_parse failed\n");
+
+ memcpy(&node_group_config,
+ ptc->qtm_mb + ATMEL_QTM_MB_NODE_GROUP_CONFIG_OFFSET,
+ sizeof(node_group_config));
+
+ /* Start QTM. */
+ qtm_cmd.id = ATMEL_QTM_CMD_INIT;
+ qtm_cmd.data = node_group_config.count;
+ atmel_qtm_cmd_send(ptc, &qtm_cmd);
+ qtm_cmd.id = ATMEL_QTM_CMD_SET_ACQ_MODE_TIMER;
+ qtm_cmd.data = 20;
+ atmel_qtm_cmd_send(ptc, &qtm_cmd);
+ qtm_cmd.id = ATMEL_QTM_CMD_RUN;
+ qtm_cmd.data = node_group_config.count;
+ atmel_qtm_cmd_send(ptc, &qtm_cmd);
+}
+
+static void atmel_ppp_fw_callback(const struct firmware *fw, void *context)
+{
+ struct atmel_ptc *ptc = context;
+ int ret;
+ struct atmel_qtm_cmd cmd;
+
+ if (!fw || !fw->size) {
+ dev_err(ptc->dev, "cannot load firmware.\n");
+ release_firmware(fw);
+ device_release_driver(ptc->dev);
+ return;
+ }
+
+ /* Command sequence to start from a clean state. */
+ atmel_ppp_cmd_send(ptc, ATMEL_PPP_CMD_ABORT);
+ atmel_ppp_irq_pending_clr(ptc, ATMEL_PPP_IRQ_MASK);
+ atmel_ppp_cmd_send(ptc, ATMEL_PPP_CMD_RESET);
+
+ memcpy(ptc->firmware, fw->data, fw->size);
+ release_firmware(fw);
+
+ atmel_ppp_cmd_send(ptc, ATMEL_PPP_CMD_RUN);
+
+ cmd.id = ATMEL_QTM_CMD_FIRM_VERSION;
+ atmel_qtm_cmd_send(ptc, &cmd);
+ dev_info(ptc->dev, "firmware version: %u\n", cmd.data);
+
+ /* PPP is running, it's time to load the QTM configuration. */
+ ret = request_firmware_nowait(THIS_MODULE, 1, ATMEL_QTM_CONF_NAME, ptc->dev,
+ GFP_KERNEL, ptc, atmel_qtm_conf_callback);
+ if (ret)
+ dev_err(ptc->dev, "QTM configuration loading failed.\n");
+}
+
+static int atmel_ptc_probe(struct platform_device *pdev)
+{
+ struct atmel_ptc *ptc;
+ struct resource *res;
+ void *shared_memory;
+ int ret;
+
+ ptc = devm_kzalloc(&pdev->dev, sizeof(*ptc), GFP_KERNEL);
+ if (!ptc)
+ return -ENOMEM;
+
+ platform_set_drvdata(pdev, ptc);
+ ptc->dev = &pdev->dev;
+ ptc->dev->driver_data = ptc;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 0);
+ if (!res)
+ return -ENODEV;
+
+ shared_memory = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(shared_memory))
+ return PTR_ERR(shared_memory);
+
+ ptc->firmware = shared_memory;
+ ptc->qtm_mb = shared_memory + ATMEL_QTM_MB_OFFSET;
+
+ res = platform_get_resource(pdev, IORESOURCE_MEM, 1);
+ if (!res)
+ return -EINVAL;
+
+ ptc->ppp_regs = devm_ioremap_resource(&pdev->dev, res);
+ if (IS_ERR(ptc->ppp_regs))
+ return PTR_ERR(ptc->ppp_regs);
+
+ ptc->irq = platform_get_irq(pdev, 0);
+ if (ptc->irq <= 0) {
+ if (!ptc->irq)
+ ptc->irq = -ENXIO;
+
+ return ptc->irq;
+ }
+
+ ptc->clk_per = devm_clk_get(&pdev->dev, "ptc_clk");
+ if (IS_ERR(ptc->clk_per))
+ return PTR_ERR(ptc->clk_per);
+
+ ptc->clk_int_osc = devm_clk_get(&pdev->dev, "ptc_int_osc");
+ if (IS_ERR(ptc->clk_int_osc))
+ return PTR_ERR(ptc->clk_int_osc);
+
+ ptc->clk_slow = devm_clk_get(&pdev->dev, "slow_clk");
+ if (IS_ERR(ptc->clk_slow))
+ return PTR_ERR(ptc->clk_slow);
+
+ ret = devm_request_irq(&pdev->dev, ptc->irq, atmel_ppp_irq_handler, 0,
+ pdev->dev.driver->name, ptc);
+ if (ret)
+ return ret;
+
+ ret = clk_prepare_enable(ptc->clk_int_osc);
+ if (ret)
+ return ret;
+
+ ret = clk_prepare_enable(ptc->clk_per);
+ if (ret)
+ goto disable_clk_int_osc;
+
+ ret = clk_prepare_enable(ptc->clk_slow);
+ if (ret)
+ goto disable_clk_per;
+
+ /* Needed to avoid unexpected behaviors. */
+ memset(ptc->firmware, 0, ATMEL_QTM_MB_OFFSET + sizeof(*ptc->qtm_mb));
+ ptc->imr = 0;
+ init_completion(&ptc->ppp_ack);
+
+ /*
+ * Expose a file to give an access to the QTM mailbox to a user space
+ * application in order to configure it or to send commands.
+ */
+ ret = sysfs_create_bin_file(&pdev->dev.kobj, &atmel_ptc_qtm_mb_attr);
+ if (ret)
+ goto disable_clk_slow;
+
+ ret = request_firmware_nowait(THIS_MODULE, 1, ATMEL_PPP_FIRMWARE_NAME,
+ ptc->dev, GFP_KERNEL, ptc,
+ atmel_ppp_fw_callback);
+ if (ret) {
+ dev_err(&pdev->dev, "firmware loading failed\n");
+ ret = -EPROBE_DEFER;
+ goto remove_qtm_mb;
+ }
+
+ return 0;
+
+remove_qtm_mb:
+ sysfs_remove_bin_file(&pdev->dev.kobj, &atmel_ptc_qtm_mb_attr);
+disable_clk_slow:
+ clk_disable_unprepare(ptc->clk_slow);
+disable_clk_per:
+ clk_disable_unprepare(ptc->clk_per);
+disable_clk_int_osc:
+ clk_disable_unprepare(ptc->clk_int_osc);
+
+ return ret;
+}
+
+static int atmel_ptc_remove(struct platform_device *pdev)
+{
+ struct atmel_ptc *ptc = platform_get_drvdata(pdev);
+ int i;
+
+ if (ptc->buttons_registered)
+ input_unregister_device(ptc->buttons_input);
+
+ for (i = 0; i < ATMEL_PTC_MAX_SCROLLERS; i++) {
+ struct input_dev *scroller = ptc->scroller_input[i];
+
+ if (!scroller || !ptc->scroller_registered[i])
+ continue;
+ input_unregister_device(scroller);
+ }
+
+ sysfs_remove_bin_file(&pdev->dev.kobj, &atmel_ptc_qtm_mb_attr);
+ clk_disable_unprepare(ptc->clk_slow);
+ clk_disable_unprepare(ptc->clk_per);
+ clk_disable_unprepare(ptc->clk_int_osc);
+
+ return 0;
+}
+
+static const struct of_device_id atmel_ptc_dt_match[] = {
+ {
+ .compatible = "atmel,sama5d2-ptc",
+ }, {
+ /* sentinel */
+ }
+};
+MODULE_DEVICE_TABLE(of, atmel_ptc_dt_match);
+
+static struct platform_driver atmel_ptc_driver = {
+ .probe = atmel_ptc_probe,
+ .remove = atmel_ptc_remove,
+ .driver = {
+ .name = "atmel_ptc",
+ .of_match_table = atmel_ptc_dt_match,
+ },
+};
+module_platform_driver(atmel_ptc_driver)
+
+MODULE_AUTHOR("Ludovic Desroches <ludovic.desroches@microchip.com>");
+MODULE_DESCRIPTION("Atmel PTC subsystem");
+MODULE_LICENSE("GPL v2");
+MODULE_FIRMWARE(ATMEL_PPP_FIRMWARE_NAME);
+MODULE_FIRMWARE(ATMEL_QTM_CONF_NAME);
--
2.12.2