Hi,
On Sat, Apr 29, 2017 at 06:40:53PM +0900, Tomohiro Yoshidomi wrote:
> PSX pads can be connected directly to the SPI bus.
>
> Signed-off-by: Tomohiro Yoshidomi <sylph23k@xxxxxxxxx>
Thank you very much for making requested changes and your patience. I
think we just need a few finishing touches and we can commit this
driver.
> ---
> drivers/input/joystick/Kconfig | 17 ++
> drivers/input/joystick/Makefile | 1 +
> drivers/input/joystick/psxpad-spi.c | 387 ++++++++++++++++++++++++++++++++++++
> 3 files changed, 405 insertions(+)
> create mode 100644 drivers/input/joystick/psxpad-spi.c
>
> diff --git a/drivers/input/joystick/Kconfig b/drivers/input/joystick/Kconfig
> index 4215b538..bfbda643 100644
> --- a/drivers/input/joystick/Kconfig
> +++ b/drivers/input/joystick/Kconfig
> @@ -330,4 +330,21 @@ config JOYSTICK_MAPLE
> To compile this as a module choose M here: the module will be called
> maplecontrol.
>
> +config JOYSTICK_PSXPAD_SPI
> + tristate "PSX (Play Station 1/2) pad with SPI Bus Driver"
Let's call this "PSX (Play Station 1/2) gamepad on SPI bus"
> + depends on SPI
> + select INPUT_POLLDEV
> + help
> + Say Y here if you connect PSX (PS1/2) pad with SPI Interface.
"Say Y here if you wish to connect PSX (PS1/2) pad via SPI interface."
> +
> + To compile this driver as a module, choose M here: the
> + module will be called psxpad-spi.
> +
> +config JOYSTICK_PSXPAD_SPI_FF
> + bool "PSX pad with SPI Bus rumble support"
Let's call it "PSX gamepad force feedback (rumble) support"
> + depends on JOYSTICK_PSXPAD_SPI
> + select INPUT_FF_MEMLESS
> + help
> + Say Y here if you want to take advantage of PSX pad rumble features.
> +
> endif
> diff --git a/drivers/input/joystick/Makefile b/drivers/input/joystick/Makefile
> index 92dc0de9..496fd56b 100644
> --- a/drivers/input/joystick/Makefile
> +++ b/drivers/input/joystick/Makefile
> @@ -21,6 +21,7 @@ obj-$(CONFIG_JOYSTICK_INTERACT) += interact.o
> obj-$(CONFIG_JOYSTICK_JOYDUMP) += joydump.o
> obj-$(CONFIG_JOYSTICK_MAGELLAN) += magellan.o
> obj-$(CONFIG_JOYSTICK_MAPLE) += maplecontrol.o
> +obj-$(CONFIG_JOYSTICK_PSXPAD_SPI) += psxpad-spi.o
> obj-$(CONFIG_JOYSTICK_SIDEWINDER) += sidewinder.o
> obj-$(CONFIG_JOYSTICK_SPACEBALL) += spaceball.o
> obj-$(CONFIG_JOYSTICK_SPACEORB) += spaceorb.o
> diff --git a/drivers/input/joystick/psxpad-spi.c b/drivers/input/joystick/psxpad-spi.c
> new file mode 100644
> index 00000000..9684839c
> --- /dev/null
> +++ b/drivers/input/joystick/psxpad-spi.c
> @@ -0,0 +1,387 @@
> +/*
> + * PSX (Play Station 1/2) pad (SPI Interface)
> + *
> + * Copyright (C) 2017 Tomohiro Yoshidomi <sylph23k@xxxxxxxxx>
> + * Licensed under the GPL-2 or later.
> + *
> + * PSX pad plug (not socket)
> + * 123 456 789
> + * (...|...|...)
> + *
> + * 1: DAT -> MISO (pullup with 1k owm to 3.3V)
> + * 2: CMD -> MOSI
> + * 3: 9V (for motor, if not use N.C.)
> + * 4: GND
> + * 5: 3.3V
> + * 6: Attention -> CS(SS)
> + * 7: SCK -> SCK
> + * 8: N.C.
> + * 9: ACK -> N.C.
> + */
> +
> +#include <linux/kernel.h>
> +#include <linux/device.h>
> +#include <linux/input.h>
> +#include <linux/input-polldev.h>
> +#include <linux/module.h>
> +#include <linux/spi/spi.h>
> +#include <linux/types.h>
> +#include <linux/pm.h>
> +#include <linux/pm_runtime.h>
> +
> +#define REVERSE_BIT(x) ((((x) & 0x80) >> 7) | (((x) & 0x40) >> 5) | (((x) & 0x20) >> 3) | (((x) & 0x10) >> 1) | (((x) & 0x08) << 1) | (((x) & 0x04) << 3) | (((x) & 0x02) << 5) | (((x) & 0x01) << 7))
> +
> +static const u8 PSX_CMD_POLL[] = {0x01, 0x42, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00};
> +static const u8 PSX_CMD_ENTER_CFG[] = {0x01, 0x43, 0x00, 0x01, 0x00, 0x00, 0x00, 0x00, 0x00};
> +static const u8 PSX_CMD_EXIT_CFG[] = {0x01, 0x43, 0x00, 0x00, 0x5A, 0x5A, 0x5A, 0x5A, 0x5A};
> +static const u8 PSX_CMD_ENABLE_MOTOR[] = {0x01, 0x4D, 0x00, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF};
> +
> +struct psxpad {
> + struct spi_device *spi;
> + struct input_polled_dev *pdev;
> + struct input_dev *idev;
> + char phys[0x20];
> + bool motor1enable;
> + bool motor2enable;
> + u8 motor1level;
> + u8 motor2level;
> + u8 pollcmd[sizeof(PSX_CMD_POLL)];
> + u8 enablemotor[sizeof(PSX_CMD_ENABLE_MOTOR)];
> + u8 sendbuf[0x20] ____cacheline_aligned;
> + u8 response[sizeof(PSX_CMD_POLL)] ____cacheline_aligned;
> +};
> +
> +static int psxpad_command(struct psxpad *pad, const u8 sendcmd[], u8 response[], const u8 sendcmdlen)
I wonder if we really need to pass "response" as a parameter here.
> +{
> + struct spi_transfer xfers = {
> + .tx_buf = pad->sendbuf,
> + .rx_buf = response,
> + .len = sendcmdlen,
> + };
> + struct spi_message msg;
> + int err;
> + u8 loc;
Let's call it "int i" - the standard loop variable.
> +
> + spi_message_init(&msg);
I do not think we need "msg" anymore.
> +
> + for (loc = 0; loc < sendcmdlen; loc++)
> + pad->sendbuf[loc] = REVERSE_BIT(sendcmd[loc]);
I think I already asked this, but I do not recall the answer: can we
supply commands with bits pre-reversed (i.e. specify PSX_CMD_POLL as
0x80, 0x42, 0x00, ... and PSX_CMD_ENTER_CFG as 0x80, 0xc2, 0x00, 0x80,
0x00, ... and so on, and reverse arguments when you supply them? See
more in psxpad_setenablemotor().
> +
> + err = spi_sync_transfer(pad->spi, &xfers, 1);
> + if (err) {
> + dev_err(&pad->idev->dev, "psxpad-spi: failed SPI xfers!!\n");
> + goto err_end;
Just return directly here:
return err;
> + }
> +
> + for (loc = 0; loc < sendcmdlen; loc++)
> + response[loc] = REVERSE_BIT(response[loc]);
We only use returned data when we poll the device. Maybe we should do
this bit-reversing outsize of psxpad_command()?
> +
> + return 0;
> +
> + err_end:
> +
> + return err;
> +}
> +
> +#ifdef CONFIG_JOYSTICK_PSXPAD_SPI_FF
> +static void psxpad_setenablemotor(struct psxpad *pad, const bool motor1enable, const bool motor2enable)
psxpad_control_motor() and there is really no need for "const" on scalar
arguments.
> +{
> + int err;
> +
> + pad->motor1enable = motor1enable;
> + pad->motor2enable = motor2enable;
> +
> + pad->enablemotor[3] = pad->motor1enable ? 0x00 : 0xFF;
> + pad->enablemotor[4] = pad->motor2enable ? 0x01 : 0xFF;
Assuming that the commands are "pre-revrsed":
memcpy(pad->sendbuf, PSX_CMD_ENTER_CFG, sizeof(PSX_CMD_ENTER_CFG);
err = psxpad_command(pad, sizeof(PSX_CMD_ENTER_CFG));
if (err) {
dev_err(&pad->spi->dev,
"%s: failed to enter config mode: %d\n",
__func__, err);
return err;
}
memcpy(pad->sendbuf, PSX_CMD_ENABLE_MOTOR, sizeof(PSX_CMD_ENABLE_MOTOR);
pad->sendbuf[3] = motor1enable ? 0x00 : 0xff;
pad->sendbuf[4] = motor2enable ? 0x80 : 0xff;
err = psxpad_command(pad, sizeof(PSX_CMD_ENABLE_MOTOR));
if (err) {
dev_err(&pad->spi->dev,
"%s: ENABLE_MOTOR command failed: %d\n",
__func__, err);
return err;
}
...
> +
> + err = psxpad_command(pad, PSX_CMD_ENTER_CFG, pad->response, sizeof(PSX_CMD_ENTER_CFG));
> + if (err) {
> + dev_err(&pad->idev->dev, "psxpad-spi: setenablemotor: enter cfg failed!!\n");
> + return;
> + }
> + err = psxpad_command(pad, pad->enablemotor, pad->response, sizeof(PSX_CMD_ENABLE_MOTOR));
> + if (err) {
> + dev_err(&pad->idev->dev, "psxpad-spi: setenablemotor: enable motor failed!!\n");
> + return;
> + }
> + err = psxpad_command(pad, PSX_CMD_EXIT_CFG, pad->response, sizeof(PSX_CMD_EXIT_CFG));
> + if (err) {
> + dev_err(&pad->idev->dev, "psxpad-spi: setenablemotor: exit config failed!!\n");
> + return;
> + }
> +}
> +
> +static void psxpad_setmotorlevel(struct psxpad *pad, const u8 motor1level, const u8 motor2level)
psxpad_set_motor_level.
> +{
> + pad->motor1level = motor1level ? 0xFF : 0x00;
> + pad->motor2level = motor2level;
> +
> + pad->pollcmd[3] = pad->motor1level;
> + pad->pollcmd[4] = pad->motor2level;
So we need to control motors both while polling and explicitly at end of
poll?
> +}
> +#else /* CONFIG_JOYSTICK_PSXPAD_SPI_FF */
> +static void psxpad_setenablemotor(struct psxpad *pad, const bool motor1enable, const bool motor2enable) { }
> +
> +static void psxpad_setmotorlevel(struct psxpad *pad, const u8 motor1level, const u8 motor2level) { }
Please try keeping within 80 columns.
> +#endif /* CONFIG_JOYSTICK_PSXPAD_SPI_FF */
> +
> +static void psxpad_spi_poll_open(struct input_polled_dev *pdev)
> +{
> + struct psxpad *pad = pdev->private;
> +
> + pm_runtime_get_sync(&pad->spi->dev);
> +}
> +
> +static void psxpad_spi_poll_close(struct input_polled_dev *pdev)
> +{
> + struct psxpad *pad = pdev->private;
> +
> + pm_runtime_put_sync(&pad->spi->dev);
> +}
> +
> +static void psxpad_spi_poll(struct input_polled_dev *pdev)
> +{
> + struct psxpad *pad = pdev->private;
> + int err;
> +
> + err = psxpad_command(pad, pad->pollcmd, pad->response, sizeof(PSX_CMD_POLL));
> + if (err) {
> + dev_err(&pad->idev->dev, "psxpad-spi: poll: poll cmd failed!!\n");
Please use pad->spi->dev in error messages, so errors are associated
with a physical device and not abstract one (inputNNN).
> + return;
> + }
> +
> + switch (pad->response[1]) {
> + case 0x73: /* analog 1 */
> + input_report_abs(pad->idev, ABS_X, pad->response[7]);
> + input_report_abs(pad->idev, ABS_Y, pad->response[8]);
> + input_report_abs(pad->idev, ABS_RX, pad->response[5]);
> + input_report_abs(pad->idev, ABS_RY, pad->response[6]);
> + input_report_key(pad->idev, BTN_DPAD_UP, (pad->response[3] & 0x10U) ? false : true);
> + input_report_key(pad->idev, BTN_DPAD_DOWN, (pad->response[3] & 0x40U) ? false : true);
Please use BIT() macro; there is also no need to convert to true/false
as input_report_key also does it.
input_report_key(pad->idev, BTN_DPAD_UP,
pad->response[3] & BIT(4));
input_report_key(pad->idev, BTN_DPAD_DOWN,
pad->response[3] & BIT(7));
and so on.
> + input_report_key(pad->idev, BTN_DPAD_LEFT, (pad->response[3] & 0x80U) ? false : true);
> + input_report_key(pad->idev, BTN_DPAD_RIGHT, (pad->response[3] & 0x20U) ? false : true);
> + input_report_key(pad->idev, BTN_X, (pad->response[4] & 0x10U) ? false : true);
> + input_report_key(pad->idev, BTN_A, (pad->response[4] & 0x20U) ? false : true);
> + input_report_key(pad->idev, BTN_B, (pad->response[4] & 0x40U) ? false : true);
> + input_report_key(pad->idev, BTN_Y, (pad->response[4] & 0x80U) ? false : true);
> + input_report_key(pad->idev, BTN_TL, (pad->response[4] & 0x04U) ? false : true);
> + input_report_key(pad->idev, BTN_TR, (pad->response[4] & 0x08U) ? false : true);
> + input_report_key(pad->idev, BTN_TL2, (pad->response[4] & 0x01U) ? false : true);
> + input_report_key(pad->idev, BTN_TR2, (pad->response[4] & 0x02U) ? false : true);
> + input_report_key(pad->idev, BTN_THUMBL, (pad->response[3] & 0x02U) ? false : true);
> + input_report_key(pad->idev, BTN_THUMBR, (pad->response[3] & 0x04U) ? false : true);
> + input_report_key(pad->idev, BTN_SELECT, (pad->response[3] & 0x01U) ? false : true);
> + input_report_key(pad->idev, BTN_START, (pad->response[3] & 0x08U) ? false : true);
> + break;
> +
> + case 0x41: /* digital */
> + input_report_abs(pad->idev, ABS_X, 0x80);
> + input_report_abs(pad->idev, ABS_Y, 0x80);
> + input_report_abs(pad->idev, ABS_RX, 0x80);
> + input_report_abs(pad->idev, ABS_RY, 0x80);
> + input_report_key(pad->idev, BTN_DPAD_UP, (pad->response[3] & 0x10U) ? false : true);
> + input_report_key(pad->idev, BTN_DPAD_DOWN, (pad->response[3] & 0x40U) ? false : true);
> + input_report_key(pad->idev, BTN_DPAD_LEFT, (pad->response[3] & 0x80U) ? false : true);
> + input_report_key(pad->idev, BTN_DPAD_RIGHT, (pad->response[3] & 0x20U) ? false : true);
> + input_report_key(pad->idev, BTN_X, (pad->response[4] & 0x10U) ? false : true);
> + input_report_key(pad->idev, BTN_A, (pad->response[4] & 0x20U) ? false : true);
> + input_report_key(pad->idev, BTN_B, (pad->response[4] & 0x40U) ? false : true);
> + input_report_key(pad->idev, BTN_Y, (pad->response[4] & 0x80U) ? false : true);
> + input_report_key(pad->idev, BTN_TL, (pad->response[4] & 0x04U) ? false : true);
> + input_report_key(pad->idev, BTN_TR, (pad->response[4] & 0x08U) ? false : true);
> + input_report_key(pad->idev, BTN_TL2, (pad->response[4] & 0x01U) ? false : true);
> + input_report_key(pad->idev, BTN_TR2, (pad->response[4] & 0x02U) ? false : true);
> + input_report_key(pad->idev, BTN_THUMBL, false);
> + input_report_key(pad->idev, BTN_THUMBR, false);
> + input_report_key(pad->idev, BTN_SELECT, (pad->response[3] & 0x01U) ? false : true);
> + input_report_key(pad->idev, BTN_START, (pad->response[3] & 0x08U) ? false : true);
> + break;
> + }
> +
> + input_sync(pad->idev);
> + psxpad_setenablemotor(pad, true, true);
> +}
> +
> +#ifdef CONFIG_JOYSTICK_PSXPAD_SPI_FF
> +static int psxpad_spi_ff(struct input_dev *idev, void *data, struct ff_effect *effect)
> +{
> + struct psxpad *pad = idev->dev.platform_data;
platform_data usually reserved for platform (board) code, not driver
data.
struct input_polled_dev *pdev = input_get_drvdata(input);
struct psxpad *pad = pdev->private;
> +
> + switch (effect->type) {
> + case FF_RUMBLE:
> + psxpad_setmotorlevel(pad, (effect->u.rumble.weak_magnitude >> 8) & 0xFFU, (effect->u.rumble.strong_magnitude >> 8) & 0xFFU);
> + break;
> + }
> +
> + return 0;
> +}
> +
> +static int psxpad_spi_init_ff(struct psxpad *pad)
> +{
> + int err;
> +
> + input_set_capability(pad->idev, EV_FF, FF_RUMBLE);
> + err = input_ff_create_memless(pad->idev, NULL, psxpad_spi_ff);
> + if (err) {
> + dev_err(&pad->idev->dev, "psxpad-spi: init_ff: ff alloc failed!!\n");
> + err = -ENOMEM;
Please do not clobber error value returned by input_ff_create_memless(),
pass it on as is.
> + }
> +
> + return err;
> +}
> +#else /* CONFIG_JOYSTICK_PSXPAD_SPI_FF */
> +static inline int psxpad_spi_init_ff(struct psxpad *pad)
> +{
> + return 0;
> +}
> +#endif /* CONFIG_JOYSTICK_PSXPAD_SPI_FF */
> +
> +static int psxpad_spi_probe(struct spi_device *spi)
> +{
> + struct psxpad *pad;
> + struct input_polled_dev *pdev;
> + struct input_dev *idev;
> + int err, i;
> +
> + pad = devm_kzalloc(&spi->dev, sizeof(struct psxpad), GFP_KERNEL);
> + if (!pad) {
> + err = -ENOMEM;
> + goto err_free_mem1;
Just
return -ENOMEM;
> + }
> + pdev = input_allocate_polled_device();
> + if (!pdev) {
> + dev_err(&spi->dev, "psxpad-spi: probe: pdev alloc failed!!\n");
No need for "psxpad-spi: " prefix - dev_err adds driver name to error
messages.
>
> + err = -ENOMEM;
> + goto err_free_mem1;
Just
return -ENOMEM;
devm will take care of freeing "pad" memory. That is is point of devm_*
API.
> + }
> + for (i = 0; i < sizeof(PSX_CMD_POLL); i++)
> + pad->pollcmd[i] = PSX_CMD_POLL[i];
> + for (i = 0; i < sizeof(PSX_CMD_ENABLE_MOTOR); i++)
> + pad->enablemotor[i] = PSX_CMD_ENABLE_MOTOR[i];
I do not think you'll need this anymore if you do what I proposed with
regard to command handling.
> +
> + /* input poll device settings */
> + pad->pdev = pdev;
> + pad->spi = spi;
> + pdev->private = pad;
> + pdev->open = psxpad_spi_poll_open;
> + pdev->close = psxpad_spi_poll_close;
> + pdev->poll = psxpad_spi_poll;
> + /* poll interval is about 60fps */
> + pdev->poll_interval = 16;
> + pdev->poll_interval_min = 8;
> + pdev->poll_interval_max = 32;
> +
> + /* input device settings */
> + idev = pdev->input;
> + pad->idev = idev;
> + idev->name = "PSX (PS1/2) pad";
> + snprintf(pad->phys, sizeof(pad->phys), "%s/input", dev_name(&spi->dev));
> + idev->id.bustype = BUS_SPI;
> + idev->dev.parent = &spi->dev;
Please drop - devm_input_allocate_polled_device should set it up for
you.
> + idev->dev.platform_data = pad;
Please drop.
> +
> + /* key/value map settings */
> + input_set_abs_params(idev, ABS_X, 0, 255, 0, 0);
> + input_set_abs_params(idev, ABS_Y, 0, 255, 0, 0);
> + input_set_abs_params(idev, ABS_RX, 0, 255, 0, 0);
> + input_set_abs_params(idev, ABS_RY, 0, 255, 0, 0);
> + input_set_capability(idev, EV_KEY, BTN_DPAD_UP);
> + input_set_capability(idev, EV_KEY, BTN_DPAD_DOWN);
> + input_set_capability(idev, EV_KEY, BTN_DPAD_LEFT);
> + input_set_capability(idev, EV_KEY, BTN_DPAD_RIGHT);
> + input_set_capability(idev, EV_KEY, BTN_A);
> + input_set_capability(idev, EV_KEY, BTN_B);
> + input_set_capability(idev, EV_KEY, BTN_X);
> + input_set_capability(idev, EV_KEY, BTN_Y);
> + input_set_capability(idev, EV_KEY, BTN_TL);
> + input_set_capability(idev, EV_KEY, BTN_TR);
> + input_set_capability(idev, EV_KEY, BTN_TL2);
> + input_set_capability(idev, EV_KEY, BTN_TR2);
> + input_set_capability(idev, EV_KEY, BTN_THUMBL);
> + input_set_capability(idev, EV_KEY, BTN_THUMBR);
> + input_set_capability(idev, EV_KEY, BTN_SELECT);
> + input_set_capability(idev, EV_KEY, BTN_START);
> +
> + /* force feedback */
> + err = psxpad_spi_init_ff(pad);
> + if (err) {
> + dev_err(&spi->dev, "psxpad-spi: probe: failed init ff!!\n");
> + err = -ENOMEM;
> + goto err_free_mem2;
return err;
> + }
> +
> + /* SPI settings */
> + spi->mode = SPI_MODE_3;
> + spi->bits_per_word = 8;
> + /* (PSX pad might be possible works 250kHz/500kHz) */
> + spi->master->min_speed_hz = 125000;
> + spi->master->max_speed_hz = 125000;
> + spi_setup(spi);
> +
> + /* pad settings */
> + psxpad_setmotorlevel(pad, 0, 0);
> +
> + /* register input poll device */
> + err = input_register_polled_device(pdev);
> + if (err) {
> + dev_err(&spi->dev, "psxpad-spi: probe: failed register!!\n");
> + goto err_free_mem2;
return err;
> + }
> +
> + pm_runtime_enable(&spi->dev);
> +
> + return 0;
> +
Code below is not needed.
> + err_free_mem2:
> + input_free_polled_device(pdev);
> +
> + err_free_mem1:
> + devm_kfree(&spi->dev, pad);
> +
> + return err;
> +}
> +
> +
> +static int psxpad_spi_remove(struct spi_device *spi)
> +{
> + return 0;
> +}
You can remove this now empty stub.
> +
> +static int __maybe_unused psxpad_spi_suspend(struct device *dev)
> +{
> + struct spi_device *spi = to_spi_device(dev);
> + struct psxpad *pad = spi_get_drvdata(spi);
> +
> + psxpad_setmotorlevel(pad, 0, 0);
> +
> + return 0;
> +}
> +
> +static int __maybe_unused psxpad_spi_resume(struct device *dev)
> +{
> + return 0;
> +}
You can remove this empty stub.
> +
> +static SIMPLE_DEV_PM_OPS(psxpad_spi_pm, psxpad_spi_suspend, psxpad_spi_resume);
> +
> +static const struct spi_device_id psxpad_spi_id[] = {
> + { "psxpad-spi", 0 },
> + { }
> +};
> +MODULE_DEVICE_TABLE(spi, psxpad_spi_id);
> +
> +static struct spi_driver psxpad_spi_driver = {
> + .driver = {
> + .name = "psxpad-spi",
> + .pm = &psxpad_spi_pm,
> + },
> + .id_table = psxpad_spi_id,
> + .probe = psxpad_spi_probe,
> + .remove = psxpad_spi_remove,
> +};
> +
> +module_spi_driver(psxpad_spi_driver);
> +
> +MODULE_AUTHOR("Tomohiro Yoshidomi <sylph23k@xxxxxxxxx>");
> +MODULE_DESCRIPTION("PSX (Play Station 1/2) pad with SPI Bus Driver");
> +MODULE_LICENSE("GPL");
> --
> 2.11.0
>
Thanks!
--
Dmitry
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