Skip to content

Commit

Permalink
rpi-ft5406: Create coherent buffer and push to firmware
Browse files Browse the repository at this point in the history
  • Loading branch information
@popcornmix
popcornmix committed Nov 14, 2016
1 parent d835ac4 commit b4cd401
Show file tree
Hide file tree
Showing 2 changed files with 101 additions and 52 deletions.
152 changes: 100 additions & 52 deletions drivers/input/touchscreen/rpi-ft5406.c
View file
Expand Up @@ -21,6 +21,7 @@
#include <linux/kthread.h>
#include <linux/platform_device.h>
#include <asm/io.h>
#include <linux/dma-mapping.h>
#include <soc/bcm2835/raspberrypi-firmware.h>

#define MAXIMUM_SUPPORTED_POINTS 10
Expand All @@ -45,6 +46,7 @@ struct ft5406 {
struct platform_device * pdev;
struct input_dev * input_dev;
void __iomem * ts_base;
dma_addr_t bus_addr;
struct ft5406_regs * regs;
struct task_struct * thread;
};
Expand Down Expand Up @@ -117,81 +119,108 @@ static int ft5406_thread(void *arg)

static int ft5406_probe(struct platform_device *pdev)
{
int ret;
struct input_dev * input_dev = input_allocate_device();
int err = 0;
struct device *dev = &pdev->dev;
struct device_node *np = dev->of_node;
struct ft5406 * ts;
struct device_node *fw_node;
struct rpi_firmware *fw;
u32 touchbuf;

dev_info(&pdev->dev, "Probing device\n");
dev_info(dev, "Probing device\n");

fw_node = of_parse_phandle(pdev->dev.of_node, "firmware", 0);
fw_node = of_parse_phandle(np, "firmware", 0);
if (!fw_node) {
dev_err(&pdev->dev, "Missing firmware node\n");
dev_err(dev, "Missing firmware node\n");
return -ENOENT;
}

fw = rpi_firmware_get(fw_node);
if (!fw)
return -EPROBE_DEFER;

ret = rpi_firmware_property(fw, RPI_FIRMWARE_FRAMEBUFFER_GET_TOUCHBUF,
&touchbuf, sizeof(touchbuf));
if (ret) {
dev_err(&pdev->dev, "Failed to get touch buffer\n");
return ret;
ts = devm_kzalloc(dev, sizeof(struct ft5406), GFP_KERNEL);
if (!ts) {
dev_err(dev, "Failed to allocate memory\n");
return -ENOMEM;
}

if (!touchbuf) {
dev_err(&pdev->dev, "Touchscreen not detected\n");
return -ENODEV;
ts->input_dev = input_allocate_device();
if (!ts->input_dev) {
dev_err(dev, "Failed to allocate input device\n");
return -ENOMEM;
}

dev_dbg(&pdev->dev, "Got TS buffer 0x%x\n", touchbuf);
ts->ts_base = dma_zalloc_coherent(NULL, PAGE_SIZE, &ts->bus_addr, GFP_KERNEL);

This comment has been minimized.

Sign in to view

Copy link
@notro

notro Nov 14, 2016

Contributor

The same issue with struct device here as well.
I can't argue with something that works, but it's really strange that it does work.
vchiq for instance didn't work before I added dev on the dma buffer allocation, and that one also passes the bus address to the firmware.

This comment has been minimized.

Sign in to view

Copy link
@popcornmix

popcornmix Nov 14, 2016

Author Collaborator

Feel free to point out things that look suspicious. Working but suspicious code can come back to bite you.
I've pushed another fixup commit.
if (!ts->ts_base) {
pr_err("[%s]: failed to dma_alloc_coherent(%ld)\n",
__func__, PAGE_SIZE);
err = -ENOMEM;
goto out;
}

ts = kzalloc(sizeof(struct ft5406), GFP_KERNEL);
touchbuf = (u32)ts->bus_addr;
err = rpi_firmware_property(fw, RPI_FIRMWARE_FRAMEBUFFER_SET_TOUCHBUF,
&touchbuf, sizeof(touchbuf));

if (!ts || !input_dev) {
ret = -ENOMEM;
dev_err(&pdev->dev, "Failed to allocate memory\n");
return ret;
if (err || touchbuf != 0) {
dev_warn(dev, "Failed to set touchbuf, trying to get err:%x\n", err);
dma_free_coherent(NULL, PAGE_SIZE, ts->ts_base, ts->bus_addr);
ts->ts_base = 0;
ts->bus_addr = 0;
}

if (!ts->ts_base) {
dev_warn(dev, "set failed, trying get (err:%d touchbuf:%x virt:%p bus:%x)\n", err, touchbuf, ts->ts_base, ts->bus_addr);

err = rpi_firmware_property(fw, RPI_FIRMWARE_FRAMEBUFFER_GET_TOUCHBUF,
&touchbuf, sizeof(touchbuf));
if (err) {
dev_err(dev, "Failed to get touch buffer\n");
goto out;
}

if (!touchbuf) {
dev_err(dev, "Touchscreen not detected\n");
err = -ENODEV;
goto out;
}

dev_dbg(dev, "Got TS buffer 0x%x\n", touchbuf);

// mmap the physical memory
touchbuf &= ~0xc0000000;
ts->ts_base = ioremap(touchbuf, sizeof(*ts->regs));
if (ts->ts_base == NULL)
{
dev_err(dev, "Failed to map physical address\n");
err = -ENOMEM;
goto out;
}
}
ts->input_dev = input_dev;
platform_set_drvdata(pdev, ts);
ts->pdev = pdev;

input_dev->name = "FT5406 memory based driver";
ts->input_dev->name = "FT5406 memory based driver";

__set_bit(EV_KEY, input_dev->evbit);
__set_bit(EV_SYN, input_dev->evbit);
__set_bit(EV_ABS, input_dev->evbit);
__set_bit(EV_KEY, ts->input_dev->evbit);
__set_bit(EV_SYN, ts->input_dev->evbit);
__set_bit(EV_ABS, ts->input_dev->evbit);

input_set_abs_params(input_dev, ABS_MT_POSITION_X, 0,
input_set_abs_params(ts->input_dev, ABS_MT_POSITION_X, 0,
SCREEN_WIDTH, 0, 0);
input_set_abs_params(input_dev, ABS_MT_POSITION_Y, 0,
input_set_abs_params(ts->input_dev, ABS_MT_POSITION_Y, 0,
SCREEN_HEIGHT, 0, 0);

input_mt_init_slots(input_dev, MAXIMUM_SUPPORTED_POINTS, INPUT_MT_DIRECT);
input_mt_init_slots(ts->input_dev, MAXIMUM_SUPPORTED_POINTS, INPUT_MT_DIRECT);

input_set_drvdata(input_dev, ts);
input_set_drvdata(ts->input_dev, ts);

ret = input_register_device(input_dev);
if (ret) {
dev_err(&pdev->dev, "could not register input device, %d\n",
ret);
return ret;
}

// mmap the physical memory
touchbuf &= ~0xc0000000;
ts->ts_base = ioremap(touchbuf, sizeof(*ts->regs));
if(ts->ts_base == NULL)
{
dev_err(&pdev->dev, "Failed to map physical address\n");
input_unregister_device(input_dev);
kzfree(ts);
return -ENOMEM;
err = input_register_device(ts->input_dev);
if (err) {
dev_err(dev, "could not register input device, %d\n",
err);
goto out;
}

ts->regs = (struct ft5406_regs *) ts->ts_base;
Expand All @@ -200,25 +229,44 @@ static int ft5406_probe(struct platform_device *pdev)
ts->thread = kthread_run(ft5406_thread, ts, "ft5406");
if(ts->thread == NULL)
{
dev_err(&pdev->dev, "Failed to create kernel thread");
iounmap(ts->ts_base);
input_unregister_device(input_dev);
kzfree(ts);
dev_err(dev, "Failed to create kernel thread");
err = -ENOMEM;
goto out;
}

return 0;

out:
if (ts->bus_addr) {
dma_free_coherent(NULL, PAGE_SIZE, ts->ts_base, ts->bus_addr);
ts->bus_addr = 0;
ts->ts_base = NULL;
} else if (ts->ts_base) {
iounmap(ts->ts_base);
ts->ts_base = NULL;
}
if (ts->input_dev) {
input_unregister_device(ts->input_dev);
ts->input_dev = NULL;
}
return err;
}

static int ft5406_remove(struct platform_device *pdev)
{
struct device *dev = &pdev->dev;
struct ft5406 *ts = (struct ft5406 *) platform_get_drvdata(pdev);

dev_info(&pdev->dev, "Removing rpi-ft5406\n");
dev_info(dev, "Removing rpi-ft5406\n");

kthread_stop(ts->thread);
iounmap(ts->ts_base);
input_unregister_device(ts->input_dev);
kzfree(ts);

if (ts->bus_addr)
dma_free_coherent(dev, PAGE_SIZE, ts->ts_base, ts->bus_addr);
else if (ts->ts_base)
iounmap(ts->ts_base);
if (ts->input_dev)
input_unregister_device(ts->input_dev);

return 0;
}
Expand Down
1 change: 1 addition & 0 deletions include/soc/bcm2835/raspberrypi-firmware.h
View file
Expand Up @@ -115,6 +115,7 @@ enum rpi_firmware_property_tag {
RPI_FIRMWARE_FRAMEBUFFER_SET_VIRTUAL_OFFSET = 0x00048009,
RPI_FIRMWARE_FRAMEBUFFER_SET_OVERSCAN = 0x0004800a,
RPI_FIRMWARE_FRAMEBUFFER_SET_PALETTE = 0x0004800b,
RPI_FIRMWARE_FRAMEBUFFER_SET_TOUCHBUF = 0x0004801f,
RPI_FIRMWARE_FRAMEBUFFER_SET_VSYNC = 0x0004800e,
RPI_FIRMWARE_FRAMEBUFFER_SET_BACKLIGHT = 0x0004800f,

Expand Down

0 comments on commit b4cd401

Please sign in to comment.