This patch series adds a set of drivers for operating the Sense HAT
peripheral device. This board is an add on for the Raspberry Pi that is
designed to connect using the GPIO connector and communicate via I2C.
It features:
- a joystick
- an 8x8 RGB LED matrix display
- a whole bunch of environmental sensors with their own drivers
(those are already in upstream Linux)
This is a refactor of the work of Serge Schneider, the author of a
version of this driver that is currently in the Raspberry Pi downstream
kernel. We modified his code to make it suitable for upstream Linux.
A couple of tests are available for the driver in the test folder in
this repo: https://github.com/underground-software/sensehat.git
- sensehat_joystick_test logs the input events from the
joystick to the console
- sensehat_display_test displays various solid colors on
the LED panel.
- full_sensehat_test displays a single lit cell that can be
moved with the joystick. Pressing the joystick ends the
program.
For more information about the Sense HAT, visit:
https://www.raspberrypi.org/products/sense-hat/
Changes since v7:
- Added missing error checks to sensehat-display and
sensehat-joystick probe functions (allocation failure,
and failure to get regmap)
- Propogated potential error from regmap write out of
the update display function so that an innability to
connect with hardware can be detected during probe
- Changed the userspace format back to individual bytes
one per color channel, three per pixel. They are now
arranged as rgb triples instead of the native format
for the hardware.
- Thanks to Miguel Ojeda for these suggestions.
Co-developed-by: Daniel Bauman <[email protected]>
Signed-off-by: Daniel Bauman <[email protected]>
Co-developed-by: Mwesigwa Guma <[email protected]>
Signed-off-by: Mwesigwa Guma <[email protected]>
Co-developed-by: Joel Savitz <[email protected]>
Signed-off-by: Joel Savitz <[email protected]>
Signed-off-by: Charles Mirabile <[email protected]>
Charles Mirabile (6):
drivers/mfd: sensehat: Add Raspberry Pi Sense HAT to simple_mfd_i2c
drivers/input/joystick: sensehat: Raspberry Pi Sense HAT joystick
driver
drivers/auxdisplay: sensehat: Raspberry Pi Sense HAT display driver
dt-bindings: mfd: sensehat: Add Raspberry Pi Sense HAT schema
MAINTAINERS: Add sensehat driver authors to MAINTAINERS
DO NOT MERGE: full sensehat device tree overlay for raspberry pi 4
.../raspberrypi,sensehat-display.yaml | 27 +++
.../input/raspberrypi,sensehat-joystick.yaml | 33 +++
.../bindings/mfd/raspberrypi,sensehat.yaml | 69 ++++++
MAINTAINERS | 11 +
drivers/auxdisplay/Kconfig | 8 +
drivers/auxdisplay/Makefile | 1 +
drivers/auxdisplay/sensehat-display.c | 205 ++++++++++++++++++
drivers/input/joystick/Kconfig | 11 +
drivers/input/joystick/Makefile | 1 +
drivers/input/joystick/sensehat-joystick.c | 137 ++++++++++++
drivers/mfd/simple-mfd-i2c.c | 1 +
sensehat.dtbs | 54 +++++
12 files changed, 558 insertions(+)
create mode 100644 Documentation/devicetree/bindings/auxdisplay/raspberrypi,sensehat-display.yaml
create mode 100644 Documentation/devicetree/bindings/input/raspberrypi,sensehat-joystick.yaml
create mode 100644 Documentation/devicetree/bindings/mfd/raspberrypi,sensehat.yaml
create mode 100644 drivers/auxdisplay/sensehat-display.c
create mode 100644 drivers/input/joystick/sensehat-joystick.c
create mode 100644 sensehat.dtbs
--
2.31.1
This patch adds the driver for the 8x8 RGB LED matrix display
on the Sense HAT. It appears as a character device named sense-hat
in /dev/. That special file is 128 bytes large and contains 64
RGB565 triples (2 bytes each) one for each pixel.
Co-developed-by: Daniel Bauman <[email protected]>
Signed-off-by: Daniel Bauman <[email protected]>
Co-developed-by: Mwesigwa Guma <[email protected]>
Signed-off-by: Mwesigwa Guma <[email protected]>
Co-developed-by: Joel Savitz <[email protected]>
Signed-off-by: Joel Savitz <[email protected]>
Signed-off-by: Charles Mirabile <[email protected]>
---
drivers/auxdisplay/Kconfig | 8 +
drivers/auxdisplay/Makefile | 1 +
drivers/auxdisplay/sensehat-display.c | 205 ++++++++++++++++++++++++++
3 files changed, 214 insertions(+)
create mode 100644 drivers/auxdisplay/sensehat-display.c
diff --git a/drivers/auxdisplay/Kconfig b/drivers/auxdisplay/Kconfig
index 64012cda4d12..9bad1aade7a0 100644
--- a/drivers/auxdisplay/Kconfig
+++ b/drivers/auxdisplay/Kconfig
@@ -203,6 +203,14 @@ config ARM_CHARLCD
line and the Linux version on the second line, but that's
still useful.
+config SENSEHAT_DISPLAY
+ tristate "Raspberry Pi Sense HAT display driver"
+ depends on I2C
+ select MFD_SIMPLE_MFD_I2C
+ help
+ This is a driver for the Raspberry Pi Sensehat 8x8 RBG-LED matrix
+ you can access it as a misc device at /dev/sense-hat
+
menuconfig PARPORT_PANEL
tristate "Parallel port LCD/Keypad Panel support"
depends on PARPORT
diff --git a/drivers/auxdisplay/Makefile b/drivers/auxdisplay/Makefile
index 6968ed4d3f0a..30b2b7934046 100644
--- a/drivers/auxdisplay/Makefile
+++ b/drivers/auxdisplay/Makefile
@@ -14,3 +14,4 @@ obj-$(CONFIG_HT16K33) += ht16k33.o
obj-$(CONFIG_PARPORT_PANEL) += panel.o
obj-$(CONFIG_LCD2S) += lcd2s.o
obj-$(CONFIG_LINEDISP) += line-display.o
+obj-$(CONFIG_SENSEHAT_DISPLAY) += sensehat-display.o
diff --git a/drivers/auxdisplay/sensehat-display.c b/drivers/auxdisplay/sensehat-display.c
new file mode 100644
index 000000000000..9faaee5cde8a
--- /dev/null
+++ b/drivers/auxdisplay/sensehat-display.c
@@ -0,0 +1,205 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Raspberry Pi Sense HAT 8x8 LED matrix display driver
+ * http://raspberrypi.org
+ *
+ * Copyright (C) 2015 Raspberry Pi
+ * Copyright (C) 2021 Charles Mirabile, Mwesigwa Guma, Joel Savitz
+ *
+ * Original Author: Serge Schneider
+ * Revised for upstream Linux by: Charles Mirabile, Mwesigwa Guma, Joel Savitz
+ */
+
+#include <linux/module.h>
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/string.h>
+#include <linux/mm.h>
+#include <linux/slab.h>
+#include <linux/uaccess.h>
+#include <linux/delay.h>
+#include <linux/init.h>
+#include <linux/platform_device.h>
+#include <linux/mod_devicetable.h>
+#include <linux/miscdevice.h>
+#include <linux/regmap.h>
+#include <linux/property.h>
+
+#define DISPLAY_SMB_REG 0x00
+#define RGB_555_MASK 0x1f
+#define NUM_LEDS 8
+#define NUM_CHANNELS 3
+
+struct sensehat_display {
+ struct platform_device *pdev;
+ struct miscdevice mdev;
+ struct mutex rw_mtx;
+ u8 vmem[NUM_LEDS][NUM_LEDS][NUM_CHANNELS];
+ struct regmap *regmap;
+};
+
+#define VMEM_SIZE sizeof_field(struct sensehat_display, vmem)
+
+
+static int sensehat_update_display(struct sensehat_display *display)
+{
+ int i, j, k, ret;
+ u8 buff[NUM_LEDS][NUM_CHANNELS][NUM_LEDS];
+
+ for (i = 0; i < NUM_LEDS; ++i)
+ for (j = 0; j < NUM_LEDS; ++j)
+ for (k = 0; k < NUM_CHANNELS; ++k)
+ buff[i][k][j] =
+ display->vmem[i][j][k] & RGB_555_MASK;
+
+ ret = regmap_bulk_write(display->regmap, DISPLAY_SMB_REG, buff,
+ VMEM_SIZE);
+ if (ret < 0)
+ dev_err(&display->pdev->dev,
+ "Update to 8x8 LED matrix display failed");
+ return ret;
+}
+
+static loff_t sensehat_display_llseek(struct file *filp, loff_t offset,
+ int whence)
+{
+ return fixed_size_llseek(filp, offset, whence, VMEM_SIZE);
+}
+
+static ssize_t sensehat_display_read(struct file *filp, char __user *buf,
+ size_t count, loff_t *f_pos)
+{
+ struct sensehat_display *sensehat_display =
+ container_of(filp->private_data, struct sensehat_display, mdev);
+ ssize_t ret = -EFAULT;
+
+ if (*f_pos < 0 || *f_pos >= VMEM_SIZE)
+ return 0;
+ count = min_t(size_t, count, VMEM_SIZE - *f_pos);
+
+ if (mutex_lock_interruptible(&sensehat_display->rw_mtx))
+ return -ERESTARTSYS;
+ if (copy_to_user(buf, *f_pos + (u8 *)sensehat_display->vmem, count))
+ goto out;
+ *f_pos += count;
+ ret = count;
+out:
+ mutex_unlock(&sensehat_display->rw_mtx);
+ return ret;
+}
+
+static ssize_t sensehat_display_write(struct file *filp, const char __user *buf,
+ size_t count, loff_t *f_pos)
+{
+ struct sensehat_display *sensehat_display =
+ container_of(filp->private_data, struct sensehat_display, mdev);
+ int ret = -EFAULT;
+
+ if (*f_pos < 0 || *f_pos >= VMEM_SIZE)
+ return -EFBIG;
+ count = min_t(size_t, count, VMEM_SIZE - *f_pos);
+
+ if (mutex_lock_interruptible(&sensehat_display->rw_mtx))
+ return -ERESTARTSYS;
+ if (copy_from_user(*f_pos + (u8 *)sensehat_display->vmem, buf, count))
+ goto out;
+ ret = sensehat_update_display(sensehat_display);
+ if (ret < 0) {
+ ret = -EIO;
+ goto out;
+ }
+ *f_pos += count;
+ ret = count;
+out:
+ mutex_unlock(&sensehat_display->rw_mtx);
+ return ret;
+}
+
+static const struct file_operations sensehat_display_fops = {
+ .owner = THIS_MODULE,
+ .llseek = sensehat_display_llseek,
+ .read = sensehat_display_read,
+ .write = sensehat_display_write,
+};
+
+static int sensehat_display_probe(struct platform_device *pdev)
+{
+ int ret;
+
+ struct sensehat_display *sensehat_display =
+ devm_kmalloc(&pdev->dev, sizeof(*sensehat_display), GFP_KERNEL);
+ if (!sensehat_display)
+ return -ENOMEM;
+
+ sensehat_display->pdev = pdev;
+
+ dev_set_drvdata(&pdev->dev, sensehat_display);
+
+ sensehat_display->regmap = dev_get_regmap(pdev->dev.parent, NULL);
+ if (!sensehat_display->regmap) {
+ dev_err(&pdev->dev,
+ "unable to get sensehat regmap");
+ return -ENODEV;
+ }
+
+ memset(sensehat_display->vmem, 0, VMEM_SIZE);
+
+ mutex_init(&sensehat_display->rw_mtx);
+
+ ret = sensehat_update_display(sensehat_display);
+ if (ret < 0) {
+ dev_err(&pdev->dev,
+ "Could not communicate with sensehat");
+ return ret;
+ }
+
+ sensehat_display->mdev = (struct miscdevice){
+ .minor = MISC_DYNAMIC_MINOR,
+ .name = "sense-hat",
+ .mode = 0666,
+ .fops = &sensehat_display_fops,
+ };
+
+ ret = misc_register(&sensehat_display->mdev);
+ if (ret < 0) {
+ dev_err(&pdev->dev,
+ "Could not register 8x8 LED matrix display.");
+ return ret;
+ }
+
+ dev_info(&pdev->dev,
+ "8x8 LED matrix display registered with minor number %i",
+ sensehat_display->mdev.minor);
+
+ return 0;
+}
+
+static int sensehat_display_remove(struct platform_device *pdev)
+{
+ struct sensehat_display *sensehat_display = dev_get_drvdata(&pdev->dev);
+
+ misc_deregister(&sensehat_display->mdev);
+ return 0;
+}
+
+static const struct of_device_id sensehat_display_device_id[] = {
+ { .compatible = "raspberrypi,sensehat-display" },
+ {},
+};
+MODULE_DEVICE_TABLE(of, sensehat_display_device_id);
+
+static struct platform_driver sensehat_display_driver = {
+ .probe = sensehat_display_probe,
+ .remove = sensehat_display_remove,
+ .driver = {
+ .name = "sensehat-display",
+ .of_match_table = sensehat_display_device_id,
+ },
+};
+
+module_platform_driver(sensehat_display_driver);
+
+MODULE_DESCRIPTION("Raspberry Pi Sense HAT 8x8 LED matrix display driver");
+MODULE_AUTHOR("Charles Mirabile <[email protected]>");
+MODULE_AUTHOR("Serge Schneider <[email protected]>");
+MODULE_LICENSE("GPL");
--
2.31.1
This patch adds the driver for the Sense HAT joystick. It outputs BTN_DPAD
key events when moved in any of the four directions and the BTN_SELECT
event when depressed.
Co-developed-by: Daniel Bauman <[email protected]>
Signed-off-by: Daniel Bauman <[email protected]>
Co-developed-by: Mwesigwa Guma <[email protected]>
Signed-off-by: Mwesigwa Guma <[email protected]>
Co-developed-by: Joel Savitz <[email protected]>
Signed-off-by: Joel Savitz <[email protected]>
Signed-off-by: Charles Mirabile <[email protected]>
---
drivers/input/joystick/Kconfig | 11 ++
drivers/input/joystick/Makefile | 1 +
drivers/input/joystick/sensehat-joystick.c | 137 +++++++++++++++++++++
3 files changed, 149 insertions(+)
create mode 100644 drivers/input/joystick/sensehat-joystick.c
diff --git a/drivers/input/joystick/Kconfig b/drivers/input/joystick/Kconfig
index 3b23078bc7b5..505a032e2786 100644
--- a/drivers/input/joystick/Kconfig
+++ b/drivers/input/joystick/Kconfig
@@ -399,4 +399,15 @@ config JOYSTICK_N64
Say Y here if you want enable support for the four
built-in controller ports on the Nintendo 64 console.
+config JOYSTICK_SENSEHAT
+ tristate "Raspberry Pi Sense HAT joystick"
+ depends on INPUT && I2C
+ select MFD_SIMPLE_MFD_I2C
+ help
+ Say Y here if you want to enable the driver for the
+ the Raspberry Pi Sense HAT.
+
+ To compile this driver as a module, choose M here: the
+ module will be called sensehat_joystick.
+
endif
diff --git a/drivers/input/joystick/Makefile b/drivers/input/joystick/Makefile
index 5174b8aba2dd..39c8b5c6e5ae 100644
--- a/drivers/input/joystick/Makefile
+++ b/drivers/input/joystick/Makefile
@@ -28,6 +28,7 @@ obj-$(CONFIG_JOYSTICK_N64) += n64joy.o
obj-$(CONFIG_JOYSTICK_PSXPAD_SPI) += psxpad-spi.o
obj-$(CONFIG_JOYSTICK_PXRC) += pxrc.o
obj-$(CONFIG_JOYSTICK_QWIIC) += qwiic-joystick.o
+obj-$(CONFIG_JOYSTICK_SENSEHAT) += sensehat-joystick.o
obj-$(CONFIG_JOYSTICK_SIDEWINDER) += sidewinder.o
obj-$(CONFIG_JOYSTICK_SPACEBALL) += spaceball.o
obj-$(CONFIG_JOYSTICK_SPACEORB) += spaceorb.o
diff --git a/drivers/input/joystick/sensehat-joystick.c b/drivers/input/joystick/sensehat-joystick.c
new file mode 100644
index 000000000000..6fed6004f464
--- /dev/null
+++ b/drivers/input/joystick/sensehat-joystick.c
@@ -0,0 +1,137 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Raspberry Pi Sense HAT joystick driver
+ * http://raspberrypi.org
+ *
+ * Copyright (C) 2015 Raspberry Pi
+ * Copyright (C) 2021 Charles Mirabile, Mwesigwa Guma, Joel Savitz
+ *
+ * Original Author: Serge Schneider
+ * Revised for upstream Linux by: Charles Mirabile, Mwesigwa Guma, Joel Savitz
+ */
+
+#include <linux/module.h>
+#include <linux/input.h>
+#include <linux/i2c.h>
+#include <linux/interrupt.h>
+#include <linux/platform_device.h>
+#include <linux/regmap.h>
+#include <linux/property.h>
+
+#define JOYSTICK_SMB_REG 0xf2
+
+struct sensehat_joystick {
+ struct platform_device *pdev;
+ struct input_dev *keys_dev;
+ unsigned long prev_states;
+ struct regmap *regmap;
+};
+
+static const unsigned int keymap[] = {
+ BTN_DPAD_DOWN, BTN_DPAD_RIGHT, BTN_DPAD_UP, BTN_SELECT, BTN_DPAD_LEFT,
+};
+
+static irqreturn_t sensehat_joystick_report(int n, void *cookie)
+{
+ int i, error, keys;
+ struct sensehat_joystick *sensehat_joystick = cookie;
+ unsigned long curr_states, changes;
+
+ error = regmap_read(sensehat_joystick->regmap, JOYSTICK_SMB_REG, &keys);
+ if (error < 0) {
+ dev_err(&sensehat_joystick->pdev->dev,
+ "Failed to read joystick state: %d", error);
+ return IRQ_NONE;
+ }
+ curr_states = keys;
+ bitmap_xor(&changes, &curr_states, &sensehat_joystick->prev_states,
+ ARRAY_SIZE(keymap));
+
+ for_each_set_bit(i, &changes, ARRAY_SIZE(keymap)) {
+ input_report_key(sensehat_joystick->keys_dev, keymap[i],
+ curr_states & BIT(i));
+ }
+
+ input_sync(sensehat_joystick->keys_dev);
+ sensehat_joystick->prev_states = keys;
+ return IRQ_HANDLED;
+}
+
+static int sensehat_joystick_probe(struct platform_device *pdev)
+{
+ int error, i, irq;
+ struct sensehat_joystick *sensehat_joystick = devm_kzalloc(
+ &pdev->dev, sizeof(*sensehat_joystick), GFP_KERNEL);
+ if (!sensehat_joystick)
+ return -ENOMEM;
+
+ sensehat_joystick->pdev = pdev;
+
+ sensehat_joystick->regmap = dev_get_regmap(sensehat_joystick->pdev->dev.parent, NULL);
+ if (!sensehat_joystick->regmap) {
+ dev_err(&pdev->dev,
+ "unable to get sensehat regmap");
+ return -ENODEV;
+ }
+
+
+ sensehat_joystick->keys_dev = devm_input_allocate_device(&pdev->dev);
+ if (!sensehat_joystick->keys_dev) {
+ dev_err(&pdev->dev, "Could not allocate input device.");
+ return -ENOMEM;
+ }
+
+ for (i = 0; i < ARRAY_SIZE(keymap); i++)
+ set_bit(keymap[i], sensehat_joystick->keys_dev->keybit);
+
+ sensehat_joystick->keys_dev->name = "Raspberry Pi Sense HAT Joystick";
+ sensehat_joystick->keys_dev->phys = "sensehat-joystick/input0";
+ sensehat_joystick->keys_dev->id.bustype = BUS_I2C;
+ sensehat_joystick->keys_dev->evbit[0] =
+ BIT_MASK(EV_KEY) | BIT_MASK(EV_REP);
+
+ error = input_register_device(sensehat_joystick->keys_dev);
+ if (error) {
+ dev_err(&pdev->dev, "Could not register input device.");
+ return error;
+ }
+
+ irq = platform_get_irq(pdev, 0);
+ if (irq < 0) {
+ dev_err(&pdev->dev, "Could not retrieve interrupt request.");
+ return irq;
+ }
+
+ error = devm_request_threaded_irq(&pdev->dev, irq, NULL,
+ sensehat_joystick_report,
+ IRQF_ONESHOT, "keys",
+ sensehat_joystick);
+
+ if (error) {
+ dev_err(&pdev->dev, "IRQ request failed.");
+ return error;
+ }
+
+ return 0;
+}
+
+static const struct of_device_id sensehat_joystick_device_id[] = {
+ { .compatible = "raspberrypi,sensehat-joystick" },
+ {},
+};
+MODULE_DEVICE_TABLE(of, sensehat_joystick_device_id);
+
+static struct platform_driver sensehat_joystick_driver = {
+ .probe = sensehat_joystick_probe,
+ .driver = {
+ .name = "sensehat-joystick",
+ .of_match_table = sensehat_joystick_device_id,
+ },
+};
+
+module_platform_driver(sensehat_joystick_driver);
+
+MODULE_DESCRIPTION("Raspberry Pi Sense HAT joystick driver");
+MODULE_AUTHOR("Charles Mirabile <[email protected]>");
+MODULE_AUTHOR("Serge Schneider <[email protected]>");
+MODULE_LICENSE("GPL");
--
2.31.1