[RFC PATCH] drivers: Raspbery Pi Sense Hat
Joel Savitz
jsavitz at redhat.com
Thu Apr 8 01:03:53 BST 2021
From: Joel Savitz <joelsavitz at gmail.com>
This is a forward port of the Rapsberry Pi Sense Hat driver from the
downstream Raspberry Pi kernel tree.
I have slightly consolidated things and done some quick testing of this
driver on Fedora (which comes with the device tree blobs), and I want to
do a bit more testing before submiting the driver for inclusion in
mainline Linux.
I would like to get some feedback from the community on what may need to
be improved, fixed, or changed as early as possible, so this is a request
for comments.
Signed-off-by: Joel Savitz <joelsavitz at gmail.com>
---
drivers/input/joystick/Kconfig | 8 +
drivers/input/joystick/Makefile | 1 +
drivers/input/joystick/rpisense-js.c | 147 ++++++++++++++
drivers/mfd/Kconfig | 8 +
drivers/mfd/Makefile | 1 +
drivers/mfd/rpisense-core.c | 162 +++++++++++++++
drivers/video/fbdev/Kconfig | 13 ++
drivers/video/fbdev/Makefile | 1 +
drivers/video/fbdev/rpisense-fb.c | 291 +++++++++++++++++++++++++++
include/linux/mfd/rpisense.h | 66 ++++++
10 files changed, 698 insertions(+)
create mode 100644 drivers/input/joystick/rpisense-js.c
create mode 100644 drivers/mfd/rpisense-core.c
create mode 100644 drivers/video/fbdev/rpisense-fb.c
create mode 100644 include/linux/mfd/rpisense.h
diff --git a/drivers/input/joystick/Kconfig b/drivers/input/joystick/Kconfig
index 5e38899058c1..1c0025c22bf4 100644
--- a/drivers/input/joystick/Kconfig
+++ b/drivers/input/joystick/Kconfig
@@ -389,4 +389,12 @@ 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_RPISENSE
+ tristate "Raspberry Pi Sense HAT joystick"
+ depends on GPIOLIB && INPUT
+ select MFD_RPISENSE_CORE
+
+ help
+ This is the joystick driver for the Raspberry Pi Sense HAT
+
endif
diff --git a/drivers/input/joystick/Makefile b/drivers/input/joystick/Makefile
index 31d720c9e493..b227e98cd179 100644
--- a/drivers/input/joystick/Makefile
+++ b/drivers/input/joystick/Makefile
@@ -27,6 +27,7 @@ obj-$(CONFIG_JOYSTICK_MAPLE) += maplecontrol.o
obj-$(CONFIG_JOYSTICK_N64) += n64joy.o
obj-$(CONFIG_JOYSTICK_PSXPAD_SPI) += psxpad-spi.o
obj-$(CONFIG_JOYSTICK_PXRC) += pxrc.o
+obj-$(CONFIG_JOYSTICK_RPISENSE) += rpisense-js.o
obj-$(CONFIG_JOYSTICK_SIDEWINDER) += sidewinder.o
obj-$(CONFIG_JOYSTICK_SPACEBALL) += spaceball.o
obj-$(CONFIG_JOYSTICK_SPACEORB) += spaceorb.o
diff --git a/drivers/input/joystick/rpisense-js.c b/drivers/input/joystick/rpisense-js.c
new file mode 100644
index 000000000000..41d4bd1fed46
--- /dev/null
+++ b/drivers/input/joystick/rpisense-js.c
@@ -0,0 +1,147 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Raspberry Pi Sense HAT joystick driver
+ * http://raspberrypi.org
+ *
+ * Copyright (C) 2015 Raspberry Pi
+ *
+ * Author: Serge Schneider
+ * Adapted for mainline Linux by: Joel Savitz
+ */
+
+#include <linux/module.h>
+#include <linux/mfd/rpisense.h>
+
+static struct rpisense *rpisense;
+static unsigned char keymap[5] = {KEY_DOWN, KEY_RIGHT, KEY_UP, KEY_ENTER, KEY_LEFT,};
+
+static void keys_work_fn(struct work_struct *work)
+{
+ int i;
+ static s32 prev_keys;
+ struct rpisense_js *rpisense_js = &rpisense->joystick;
+ s32 keys = rpisense_reg_read(rpisense, RPISENSE_KEYS);
+ s32 changes = keys ^ prev_keys;
+
+ prev_keys = keys;
+ for (i = 0; i < 5; i++) {
+ if (changes & 1) {
+ input_report_key(rpisense_js->keys_dev,
+ keymap[i], keys & 1);
+ }
+ changes >>= 1;
+ keys >>= 1;
+ }
+ input_sync(rpisense_js->keys_dev);
+}
+
+static irqreturn_t keys_irq_handler(int irq, void *pdev)
+{
+ struct rpisense_js *rpisense_js = &rpisense->joystick;
+
+ schedule_work(&rpisense_js->keys_work_s);
+ return IRQ_HANDLED;
+}
+
+static int rpisense_js_probe(struct platform_device *pdev)
+{
+ int ret;
+ int i;
+ struct rpisense_js *rpisense_js;
+
+ rpisense = rpisense_get_dev();
+ rpisense_js = &rpisense->joystick;
+
+ INIT_WORK(&rpisense_js->keys_work_s, keys_work_fn);
+
+ rpisense_js->keys_dev = input_allocate_device();
+ if (!rpisense_js->keys_dev) {
+ dev_err(&pdev->dev, "Could not allocate input device.\n");
+ return -ENOMEM;
+ }
+
+ rpisense_js->keys_dev->evbit[0] = BIT_MASK(EV_KEY);
+ for (i = 0; i < ARRAY_SIZE(keymap); i++) {
+ set_bit(keymap[i],
+ rpisense_js->keys_dev->keybit);
+ }
+
+ rpisense_js->keys_dev->name = "Raspberry Pi Sense HAT Joystick";
+ rpisense_js->keys_dev->phys = "rpi-sense-joy/input0";
+ rpisense_js->keys_dev->id.bustype = BUS_I2C;
+ rpisense_js->keys_dev->evbit[0] = BIT_MASK(EV_KEY) | BIT_MASK(EV_REP);
+ rpisense_js->keys_dev->keycode = keymap;
+ rpisense_js->keys_dev->keycodesize = sizeof(unsigned char);
+ rpisense_js->keys_dev->keycodemax = ARRAY_SIZE(keymap);
+
+ ret = input_register_device(rpisense_js->keys_dev);
+ if (ret) {
+ dev_err(&pdev->dev, "Could not register input device.\n");
+ goto err_keys_alloc;
+ }
+
+ ret = gpiod_direction_input(rpisense_js->keys_desc);
+ if (ret) {
+ dev_err(&pdev->dev, "Could not set keys-int direction.\n");
+ goto err_keys_reg;
+ }
+
+ rpisense_js->keys_irq = gpiod_to_irq(rpisense_js->keys_desc);
+ if (rpisense_js->keys_irq < 0) {
+ dev_err(&pdev->dev, "Could not determine keys-int IRQ.\n");
+ ret = rpisense_js->keys_irq;
+ goto err_keys_reg;
+ }
+
+ ret = devm_request_irq(&pdev->dev, rpisense_js->keys_irq,
+ keys_irq_handler, IRQF_TRIGGER_RISING,
+ "keys", &pdev->dev);
+ if (ret) {
+ dev_err(&pdev->dev, "IRQ request failed.\n");
+ goto err_keys_reg;
+ }
+ return 0;
+err_keys_reg:
+ input_unregister_device(rpisense_js->keys_dev);
+err_keys_alloc:
+ input_free_device(rpisense_js->keys_dev);
+ return ret;
+}
+
+static int rpisense_js_remove(struct platform_device *pdev)
+{
+ struct rpisense_js *rpisense_js = &rpisense->joystick;
+
+ input_unregister_device(rpisense_js->keys_dev);
+ input_free_device(rpisense_js->keys_dev);
+ return 0;
+}
+
+#ifdef CONFIG_OF
+static const struct of_device_id rpisense_js_id[] = {
+ { .compatible = "raspberrypi,rpi-sense-js" },
+ { },
+};
+MODULE_DEVICE_TABLE(of, rpisense_js_id);
+#endif
+
+static struct platform_device_id rpisense_js_device_id[] = {
+ { .name = "rpi-sense-js" },
+ { },
+};
+MODULE_DEVICE_TABLE(platform, rpisense_js_device_id);
+
+static struct platform_driver rpisense_js_driver = {
+ .probe = rpisense_js_probe,
+ .remove = rpisense_js_remove,
+ .driver = {
+ .name = "rpi-sense-js",
+ .owner = THIS_MODULE,
+ },
+};
+
+module_platform_driver(rpisense_js_driver);
+
+MODULE_DESCRIPTION("Raspberry Pi Sense HAT joystick driver");
+MODULE_AUTHOR("Serge Schneider <serge at raspberrypi.org>");
+MODULE_LICENSE("GPL");
diff --git a/drivers/mfd/Kconfig b/drivers/mfd/Kconfig
index b74efa469e90..8c309e389359 100644
--- a/drivers/mfd/Kconfig
+++ b/drivers/mfd/Kconfig
@@ -11,6 +11,14 @@ config MFD_CORE
select IRQ_DOMAIN
default n
+config MFD_RPISENSE_CORE
+ tristate "Raspberry Pi Sense HAT core functions"
+ depends on I2C
+ select MFD_CORE
+ help
+ This is the core driver for the Raspberry Pi Sense HAT. This provides
+ the necessary functions to communicate with the hardware.
+
config MFD_CS5535
tristate "AMD CS5535 and CS5536 southbridge core functions"
select MFD_CORE
diff --git a/drivers/mfd/Makefile b/drivers/mfd/Makefile
index 834f5463af28..7140a8fc36ee 100644
--- a/drivers/mfd/Makefile
+++ b/drivers/mfd/Makefile
@@ -263,6 +263,7 @@ obj-$(CONFIG_MFD_ROHM_BD71828) += rohm-bd71828.o
obj-$(CONFIG_MFD_ROHM_BD718XX) += rohm-bd718x7.o
obj-$(CONFIG_MFD_STMFX) += stmfx.o
obj-$(CONFIG_MFD_KHADAS_MCU) += khadas-mcu.o
+obj-$(CONFIG_MFD_RPISENSE_CORE) += rpisense-core.o
obj-$(CONFIG_MFD_ACER_A500_EC) += acer-ec-a500.o
obj-$(CONFIG_SGI_MFD_IOC3) += ioc3.o
diff --git a/drivers/mfd/rpisense-core.c b/drivers/mfd/rpisense-core.c
new file mode 100644
index 000000000000..aa2c394c5e67
--- /dev/null
+++ b/drivers/mfd/rpisense-core.c
@@ -0,0 +1,162 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Raspberry Pi Sense HAT core driver
+ * http://raspberrypi.org
+ *
+ * Copyright (C) 2015 Raspberry Pi
+ *
+ * Author: Serge Schneider
+ * Adapted for mainline Linux by: Joel Savitz
+ *
+ * This driver is based on wm8350 implementation.
+ */
+
+#include <linux/module.h>
+#include <linux/moduleparam.h>
+#include <linux/err.h>
+#include <linux/init.h>
+#include <linux/i2c.h>
+#include <linux/slab.h>
+
+#include <linux/mfd/rpisense.h>
+
+static struct rpisense *rpisense;
+
+static void rpisense_client_dev_register(struct rpisense *rpisense,
+ const char *name,
+ struct platform_device **pdev)
+{
+ int ret;
+
+ *pdev = platform_device_alloc(name, -1);
+ if (*pdev == NULL) {
+ dev_err(rpisense->dev, "Failed to allocate %s\n", name);
+ return;
+ }
+
+ (*pdev)->dev.parent = rpisense->dev;
+ platform_set_drvdata(*pdev, rpisense);
+ ret = platform_device_add(*pdev);
+ if (ret != 0) {
+ dev_err(rpisense->dev, "Failed to register %s: %d\n",
+ name, ret);
+ platform_device_put(*pdev);
+ *pdev = NULL;
+ }
+}
+
+static int rpisense_probe(struct i2c_client *i2c,
+ const struct i2c_device_id *id)
+{
+ int ret;
+ struct rpisense_js *rpisense_js;
+
+ rpisense = devm_kzalloc(&i2c->dev, sizeof(struct rpisense), GFP_KERNEL);
+ if (rpisense == NULL)
+ return -ENOMEM;
+
+ i2c_set_clientdata(i2c, rpisense);
+ rpisense->dev = &i2c->dev;
+ rpisense->i2c_client = i2c;
+
+ ret = rpisense_reg_read(rpisense, RPISENSE_WAI);
+ if (ret > 0) {
+ if (ret != 's')
+ return -EINVAL;
+ } else {
+ return ret;
+ }
+ ret = rpisense_reg_read(rpisense, RPISENSE_VER);
+ if (ret < 0)
+ return ret;
+
+ dev_info(rpisense->dev,
+ "Raspberry Pi Sense HAT firmware version %i\n", ret);
+
+ rpisense_js = &rpisense->joystick;
+ rpisense_js->keys_desc = devm_gpiod_get(&i2c->dev,
+ "keys-int", GPIOD_IN);
+ if (IS_ERR(rpisense_js->keys_desc)) {
+ dev_warn(&i2c->dev, "Failed to get keys-int descriptor.\n");
+ rpisense_js->keys_desc = gpio_to_desc(23);
+ if (rpisense_js->keys_desc == NULL) {
+ dev_err(&i2c->dev, "GPIO23 fallback failed.\n");
+ return PTR_ERR(rpisense_js->keys_desc);
+ }
+ }
+ rpisense_client_dev_register(rpisense, "rpi-sense-js",
+ &(rpisense->joystick.pdev));
+ rpisense_client_dev_register(rpisense, "rpi-sense-fb",
+ &(rpisense->framebuffer.pdev));
+
+ return 0;
+}
+
+static int rpisense_remove(struct i2c_client *i2c)
+{
+ struct rpisense *rpisense = i2c_get_clientdata(i2c);
+
+ platform_device_unregister(rpisense->joystick.pdev);
+ return 0;
+}
+
+struct rpisense *rpisense_get_dev(void)
+{
+ return rpisense;
+}
+EXPORT_SYMBOL_GPL(rpisense_get_dev);
+
+s32 rpisense_reg_read(struct rpisense *rpisense, int reg)
+{
+ int ret = i2c_smbus_read_byte_data(rpisense->i2c_client, reg);
+
+ if (ret < 0)
+ dev_err(rpisense->dev, "Read from reg %d failed\n", reg);
+ /* Due to the BCM270x I2C clock stretching bug, some values
+ * may have MSB set. Clear it to avoid incorrect values.
+ */
+ return ret & 0x7F;
+}
+EXPORT_SYMBOL_GPL(rpisense_reg_read);
+
+int rpisense_block_write(struct rpisense *rpisense, const char *buf, int count)
+{
+ int ret = i2c_master_send(rpisense->i2c_client, buf, count);
+
+ if (ret < 0)
+ dev_err(rpisense->dev, "Block write failed\n");
+ return ret;
+}
+EXPORT_SYMBOL_GPL(rpisense_block_write);
+
+static const struct i2c_device_id rpisense_i2c_id[] = {
+ { "rpi-sense", 0 },
+ { }
+};
+MODULE_DEVICE_TABLE(i2c, rpisense_i2c_id);
+
+#ifdef CONFIG_OF
+static const struct of_device_id rpisense_core_id[] = {
+ { .compatible = "raspberrypi,rpi-sense" },
+ { },
+};
+MODULE_DEVICE_TABLE(of, rpisense_core_id);
+#endif
+
+
+static struct i2c_driver rpisense_driver = {
+ .driver = {
+ .name = "rpi-sense",
+ .owner = THIS_MODULE,
+ },
+ .probe = rpisense_probe,
+ .remove = rpisense_remove,
+ .id_table = rpisense_i2c_id,
+};
+
+module_i2c_driver(rpisense_driver);
+
+MODULE_DESCRIPTION("Raspberry Pi Sense HAT core driver");
+MODULE_AUTHOR("Serge Schneider <serge at raspberrypi.org>");
+MODULE_LICENSE("GPL");
+
diff --git a/drivers/video/fbdev/Kconfig b/drivers/video/fbdev/Kconfig
index 4f02db65dede..2238e36e71e4 100644
--- a/drivers/video/fbdev/Kconfig
+++ b/drivers/video/fbdev/Kconfig
@@ -2236,6 +2236,19 @@ config FB_SM712
called sm712fb. If you want to compile it as a module, say M
here and read <file:Documentation/kbuild/modules.rst>.
+config FB_RPISENSE
+ tristate "Raspberry Pi Sense HAT framebuffer"
+ depends on FB
+ select MFD_RPISENSE_CORE
+ select FB_SYS_FOPS
+ select FB_SYS_FILLRECT
+ select FB_SYS_COPYAREA
+ select FB_SYS_IMAGEBLIT
+ select FB_DEFERRED_IO
+
+ help
+ This is the framebuffer driver for the Raspberry Pi Sense HAT
+
source "drivers/video/fbdev/omap/Kconfig"
source "drivers/video/fbdev/omap2/Kconfig"
source "drivers/video/fbdev/mmp/Kconfig"
diff --git a/drivers/video/fbdev/Makefile b/drivers/video/fbdev/Makefile
index 477b9624b703..5b17203b7e43 100644
--- a/drivers/video/fbdev/Makefile
+++ b/drivers/video/fbdev/Makefile
@@ -129,6 +129,7 @@ obj-$(CONFIG_FB_MX3) += mx3fb.o
obj-$(CONFIG_FB_DA8XX) += da8xx-fb.o
obj-$(CONFIG_FB_SSD1307) += ssd1307fb.o
obj-$(CONFIG_FB_SIMPLE) += simplefb.o
+obj-$(CONFIG_FB_RPISENSE) += rpisense-fb.o
# the test framebuffer is last
obj-$(CONFIG_FB_VIRTUAL) += vfb.o
diff --git a/drivers/video/fbdev/rpisense-fb.c b/drivers/video/fbdev/rpisense-fb.c
new file mode 100644
index 000000000000..a90a5ec51fd7
--- /dev/null
+++ b/drivers/video/fbdev/rpisense-fb.c
@@ -0,0 +1,291 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Raspberry Pi Sense HAT framebuffer driver
+ * http://raspberrypi.org
+ *
+ * Copyright (C) 2015 Raspberry Pi
+ *
+ * Author: Serge Schneider
+ * Adapted for mainline Linux by: 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/fb.h>
+#include <linux/init.h>
+
+#include <linux/mfd/rpisense.h>
+
+static bool lowlight;
+module_param(lowlight, bool, 0);
+MODULE_PARM_DESC(lowlight, "Reduce LED matrix brightness to one third");
+
+static struct rpisense *rpisense;
+
+struct rpisense_fb_param {
+ char __iomem *vmem;
+ u8 *vmem_work;
+ u32 vmemsize;
+ u8 *gamma;
+};
+
+static u8 gamma_default[32] = {0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x01, 0x01,
+ 0x02, 0x02, 0x03, 0x03, 0x04, 0x05, 0x06, 0x07,
+ 0x08, 0x09, 0x0A, 0x0B, 0x0C, 0x0E, 0x0F, 0x11,
+ 0x12, 0x14, 0x15, 0x17, 0x19, 0x1B, 0x1D, 0x1F,};
+
+static u8 gamma_low[32] = {0x00, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01, 0x01,
+ 0x01, 0x01, 0x01, 0x01, 0x01, 0x02, 0x02, 0x02,
+ 0x03, 0x03, 0x03, 0x04, 0x04, 0x05, 0x05, 0x06,
+ 0x06, 0x07, 0x07, 0x08, 0x08, 0x09, 0x0A, 0x0A,};
+
+static u8 gamma_user[32];
+
+static u32 pseudo_palette[16];
+
+static struct rpisense_fb_param rpisense_fb_param = {
+ .vmem = NULL,
+ .vmemsize = 128,
+ .gamma = gamma_default,
+};
+
+static struct fb_deferred_io rpisense_fb_defio;
+
+static struct fb_fix_screeninfo rpisense_fb_fix = {
+ .id = "RPi-Sense FB",
+ .type = FB_TYPE_PACKED_PIXELS,
+ .visual = FB_VISUAL_TRUECOLOR,
+ .xpanstep = 0,
+ .ypanstep = 0,
+ .ywrapstep = 0,
+ .accel = FB_ACCEL_NONE,
+ .line_length = 16,
+};
+
+static struct fb_var_screeninfo rpisense_fb_var = {
+ .xres = 8,
+ .yres = 8,
+ .xres_virtual = 8,
+ .yres_virtual = 8,
+ .bits_per_pixel = 16,
+ .red = {11, 5, 0},
+ .green = {5, 6, 0},
+ .blue = {0, 5, 0},
+};
+
+static ssize_t rpisense_fb_write(struct fb_info *info,
+ const char __user *buf, size_t count,
+ loff_t *ppos)
+{
+ ssize_t res = fb_sys_write(info, buf, count, ppos);
+
+ schedule_delayed_work(&info->deferred_work, rpisense_fb_defio.delay);
+ return res;
+}
+
+static void rpisense_fb_fillrect(struct fb_info *info,
+ const struct fb_fillrect *rect)
+{
+ sys_fillrect(info, rect);
+ schedule_delayed_work(&info->deferred_work, rpisense_fb_defio.delay);
+}
+
+static void rpisense_fb_copyarea(struct fb_info *info,
+ const struct fb_copyarea *area)
+{
+ sys_copyarea(info, area);
+ schedule_delayed_work(&info->deferred_work, rpisense_fb_defio.delay);
+}
+
+static void rpisense_fb_imageblit(struct fb_info *info,
+ const struct fb_image *image)
+{
+ sys_imageblit(info, image);
+ schedule_delayed_work(&info->deferred_work, rpisense_fb_defio.delay);
+}
+
+static void rpisense_fb_deferred_io(struct fb_info *info,
+ struct list_head *pagelist)
+{
+ int i;
+ int j;
+ u8 *vmem_work = rpisense_fb_param.vmem_work;
+ u16 *mem = (u16 *)rpisense_fb_param.vmem;
+ u8 *gamma = rpisense_fb_param.gamma;
+
+ vmem_work[0] = 0;
+ for (j = 0; j < 8; j++) {
+ for (i = 0; i < 8; i++) {
+ vmem_work[(j * 24) + i + 1] =
+ gamma[(mem[(j * 8) + i] >> 11) & 0x1F];
+ vmem_work[(j * 24) + (i + 8) + 1] =
+ gamma[(mem[(j * 8) + i] >> 6) & 0x1F];
+ vmem_work[(j * 24) + (i + 16) + 1] =
+ gamma[(mem[(j * 8) + i]) & 0x1F];
+ }
+ }
+ rpisense_block_write(rpisense, vmem_work, 193);
+}
+
+static struct fb_deferred_io rpisense_fb_defio = {
+ .delay = HZ/100,
+ .deferred_io = rpisense_fb_deferred_io,
+};
+
+static int rpisense_fb_ioctl(struct fb_info *info, unsigned int cmd,
+ unsigned long arg)
+{
+ switch (cmd) {
+ case SENSEFB_FBIOGET_GAMMA:
+ if (copy_to_user((void __user *) arg, rpisense_fb_param.gamma,
+ sizeof(u8[32])))
+ return -EFAULT;
+ return 0;
+ case SENSEFB_FBIOSET_GAMMA:
+ if (copy_from_user(gamma_user, (void __user *)arg,
+ sizeof(u8[32])))
+ return -EFAULT;
+ rpisense_fb_param.gamma = gamma_user;
+ schedule_delayed_work(&info->deferred_work,
+ rpisense_fb_defio.delay);
+ return 0;
+ case SENSEFB_FBIORESET_GAMMA:
+ switch (arg) {
+ case 0:
+ rpisense_fb_param.gamma = gamma_default;
+ break;
+ case 1:
+ rpisense_fb_param.gamma = gamma_low;
+ break;
+ case 2:
+ rpisense_fb_param.gamma = gamma_user;
+ break;
+ default:
+ return -EINVAL;
+ }
+ schedule_delayed_work(&info->deferred_work,
+ rpisense_fb_defio.delay);
+ break;
+ default:
+ return -EINVAL;
+ }
+ return 0;
+}
+
+static struct fb_ops rpisense_fb_ops = {
+ .owner = THIS_MODULE,
+ .fb_read = fb_sys_read,
+ .fb_write = rpisense_fb_write,
+ .fb_fillrect = rpisense_fb_fillrect,
+ .fb_copyarea = rpisense_fb_copyarea,
+ .fb_imageblit = rpisense_fb_imageblit,
+ .fb_ioctl = rpisense_fb_ioctl,
+};
+
+static int rpisense_fb_probe(struct platform_device *pdev)
+{
+ struct fb_info *info;
+ int ret = -ENOMEM;
+ struct rpisense_fb *rpisense_fb;
+
+ rpisense = rpisense_get_dev();
+ rpisense_fb = &rpisense->framebuffer;
+
+ rpisense_fb_param.vmem = vzalloc(rpisense_fb_param.vmemsize);
+ if (!rpisense_fb_param.vmem)
+ return ret;
+
+ rpisense_fb_param.vmem_work = devm_kmalloc(&pdev->dev, 193, GFP_KERNEL);
+ if (!rpisense_fb_param.vmem_work)
+ goto err_malloc;
+
+ info = framebuffer_alloc(0, &pdev->dev);
+ if (!info) {
+ dev_err(&pdev->dev, "Could not allocate framebuffer.\n");
+ goto err_malloc;
+ }
+ rpisense_fb->info = info;
+
+ rpisense_fb_fix.smem_start = (unsigned long)rpisense_fb_param.vmem;
+ rpisense_fb_fix.smem_len = rpisense_fb_param.vmemsize;
+
+ info->fbops = &rpisense_fb_ops;
+ info->fix = rpisense_fb_fix;
+ info->var = rpisense_fb_var;
+ info->fbdefio = &rpisense_fb_defio;
+ info->flags = FBINFO_FLAG_DEFAULT | FBINFO_VIRTFB;
+ info->screen_base = rpisense_fb_param.vmem;
+ info->screen_size = rpisense_fb_param.vmemsize;
+ info->pseudo_palette = pseudo_palette;
+
+ if (lowlight)
+ rpisense_fb_param.gamma = gamma_low;
+
+ fb_deferred_io_init(info);
+
+ ret = register_framebuffer(info);
+ if (ret < 0) {
+ dev_err(&pdev->dev, "Could not register framebuffer.\n");
+ goto err_fballoc;
+ }
+
+ fb_info(info, "%s frame buffer device\n", info->fix.id);
+ schedule_delayed_work(&info->deferred_work, rpisense_fb_defio.delay);
+ return 0;
+err_fballoc:
+ framebuffer_release(info);
+err_malloc:
+ vfree(rpisense_fb_param.vmem);
+ return ret;
+}
+
+static int rpisense_fb_remove(struct platform_device *pdev)
+{
+ struct rpisense_fb *rpisense_fb = &rpisense->framebuffer;
+ struct fb_info *info = rpisense_fb->info;
+
+ if (info) {
+ unregister_framebuffer(info);
+ fb_deferred_io_cleanup(info);
+ framebuffer_release(info);
+ vfree(rpisense_fb_param.vmem);
+ }
+
+ return 0;
+}
+
+#ifdef CONFIG_OF
+static const struct of_device_id rpisense_fb_id[] = {
+ { .compatible = "raspberrypi,rpi-sense-fb" },
+ { },
+};
+MODULE_DEVICE_TABLE(of, rpisense_fb_id);
+#endif
+
+static struct platform_device_id rpisense_fb_device_id[] = {
+ { .name = "rpi-sense-fb" },
+ { },
+};
+MODULE_DEVICE_TABLE(platform, rpisense_fb_device_id);
+
+static struct platform_driver rpisense_fb_driver = {
+ .probe = rpisense_fb_probe,
+ .remove = rpisense_fb_remove,
+ .driver = {
+ .name = "rpi-sense-fb",
+ .owner = THIS_MODULE,
+ },
+};
+
+module_platform_driver(rpisense_fb_driver);
+
+MODULE_DESCRIPTION("Raspberry Pi Sense HAT framebuffer driver");
+MODULE_AUTHOR("Serge Schneider <serge at raspberrypi.org>");
+MODULE_LICENSE("GPL");
+
diff --git a/include/linux/mfd/rpisense.h b/include/linux/mfd/rpisense.h
new file mode 100644
index 000000000000..0718b6f0eddb
--- /dev/null
+++ b/include/linux/mfd/rpisense.h
@@ -0,0 +1,66 @@
+/* SPDX-License-Identifier: GPL-2.0-or-later */
+/*
+ * Raspberry Pi Sense HAT core driver
+ * http://raspberrypi.org
+ *
+ * Copyright (C) 2015 Raspberry Pi
+ *
+ * Author: Serge Schneider
+ * Adapted for mainline Linux by: Joel Savitz
+ */
+
+#ifndef __LINUX_MFD_RPISENSE_CORE_H_
+#define __LINUX_MFD_RPISENSE_CORE_H_
+
+#include <linux/input.h>
+#include <linux/interrupt.h>
+#include <linux/gpio/consumer.h>
+#include <linux/platform_device.h>
+
+/*
+ * Register values.
+ */
+#define RPISENSE_FB 0x00
+#define RPISENSE_WAI 0xF0
+#define RPISENSE_VER 0xF1
+#define RPISENSE_KEYS 0xF2
+#define RPISENSE_EE_WP 0xF3
+
+#define RPISENSE_ID 's'
+
+#define SENSEFB_FBIO_IOC_MAGIC 0xF1
+
+#define SENSEFB_FBIOGET_GAMMA _IO(SENSEFB_FBIO_IOC_MAGIC, 0)
+#define SENSEFB_FBIOSET_GAMMA _IO(SENSEFB_FBIO_IOC_MAGIC, 1)
+#define SENSEFB_FBIORESET_GAMMA _IO(SENSEFB_FBIO_IOC_MAGIC, 2)
+
+struct rpisense_fb {
+ struct platform_device *pdev;
+ struct fb_info *info;
+};
+
+
+struct rpisense_js {
+ struct platform_device *pdev;
+ struct input_dev *keys_dev;
+ struct gpio_desc *keys_desc;
+ struct work_struct keys_work_s;
+ int keys_irq;
+};
+
+
+struct rpisense {
+ struct device *dev;
+ struct i2c_client *i2c_client;
+
+ /* Client devices */
+ struct rpisense_js joystick;
+ struct rpisense_fb framebuffer;
+};
+
+struct rpisense *rpisense_get_dev(void);
+s32 rpisense_reg_read(struct rpisense *rpisense, int reg);
+int rpisense_reg_write(struct rpisense *rpisense, int reg, u16 val);
+int rpisense_block_write(struct rpisense *rpisense, const char *buf, int count);
+
+#endif
--
2.27.0
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