[RFC PATCH] da9052_tsi: remove fifo and use delayed work

Remove the coordinate fifo and check for penup with a delayed work, instead of a watching kernel thread.

Issues: Sometimes there are well defined jitter values on the x-axys this must be more investigated. Hint: DA9052_TSI_CONT_A_REG holds some time Adjust values for TSI_SKIP and TSI_DELAY, which might have to be properly aligned to the touch events.

Signed-off-by: Michael Grzeschik m.grzeschik@pengutronix.de --- drivers/input/touchscreen/da9052_tsi.c | 245 ++++++++------------------------ 1 files changed, 61 insertions(+), 184 deletions(-)

diff --git a/drivers/input/touchscreen/da9052_tsi.c b/drivers/input/touchscreen/da9052_tsi.c index 91e051a..91d489f 100755 --- a/drivers/input/touchscreen/da9052_tsi.c +++ b/drivers/input/touchscreen/da9052_tsi.c @@ -15,47 +15,24 @@ #include <linux/input.h> #include <linux/delay.h> #include <linux/platform_device.h> -#include <linux/freezer.h> +#include <linux/sched.h> #include <linux/kthread.h> -#include <linux/kfifo.h>

#include <linux/mfd/da9052/reg.h> #include <linux/mfd/da9052/da9052.h>

-#define DA9052_ACTIVE 1 -#define DA9052_INACTIVE 0 - -#define DA9052_TSI_FIFOSIZE 640 - -enum { - DA9052_PEN_IDLE, - DA9052_PEN_DOWN, - DA9052_PEN_UP -}; - struct da9052_tsi_reg { u16 x; u16 y; };

-struct tsi_thread_type { - u8 pid; - u8 state; - struct completion notifier; - struct task_struct *thread_task; -}; - struct da9052_tsi { struct da9052 *da9052; struct input_dev *dev; - struct tsi_thread_type tsi_pen_state_thread; - struct tsi_thread_type tsi_filter_thread; - struct kfifo fifo; - struct kfifo fifo_buf; u8 pen_up_detect_interval; u32 zero_data_cnt; u32 valid_penup_count; - u8 pen_state; + struct delayed_work work; int irq_pendwn; int irq_datardy; }; @@ -71,6 +48,48 @@ static inline int da9052_ts_stop(struct da9052_tsi *tsi) return da9052_clear_bits(tsi->da9052, DA9052_TSI_CONT_A_REG, 1 << 0); }

+static void da9052_work(struct work_struct *work) +{ + struct da9052_tsi *tsi = container_of(work, struct da9052_tsi, work.work); + struct da9052 *da9052 = tsi->da9052; + int ret; + uint8_t _v; + u16 down; + + ret = da9052_reg_read(tsi->da9052, DA9052_TSI_LSB_REG); + if (ret < 0) + return; + + _v = (uint8_t) ret; + down = ((_v & 0x40) >> 6); + + if (!down) { + tsi->da9052->events_mask |= DA9052_E_TSI_READY; + tsi->da9052->events_mask &= ~DA9052_E_PEN_DOWN; + + /* Mask TSI_READY event and unmask PEN_DOWN event*/ + ret = da9052_reg_update(tsi->da9052, DA9052_IRQ_MASK_B_REG, 0x40, 0x80); + if (ret < 0) + return; + + input_report_abs(tsi->dev, ABS_PRESSURE, 0); + input_report_key(tsi->dev, BTN_TOUCH, 1); + input_sync(tsi->dev); + } else { + da9052->events_mask |= DA9052_E_PEN_DOWN; + da9052->events_mask &= ~DA9052_E_TSI_READY; + + /* Mask PEN_DOWN event and unmask TSI_READY event*/ + ret = da9052_reg_update(da9052, DA9052_IRQ_MASK_B_REG, 0x80, 0x40); + if (ret < 0) + return; + + /* start polling for touch_det to detect release */ + schedule_delayed_work(&tsi->work, HZ / 50); + } + +} + static irqreturn_t da9052_ts_pendwn_irq(int irq, void *data) { struct da9052_tsi *tsi = (struct da9052_tsi *)data; @@ -86,7 +105,10 @@ static irqreturn_t da9052_ts_pendwn_irq(int irq, void *data) return IRQ_NONE;

da9052_ts_start(tsi); - tsi->pen_state = DA9052_PEN_DOWN; + + input_report_abs(tsi->dev, ABS_PRESSURE, 1023); + input_report_key(tsi->dev, BTN_TOUCH, 0); + input_sync(tsi->dev);

return IRQ_HANDLED; } @@ -118,7 +140,10 @@ static int da9052_ts_read(struct da9052_tsi *tsi) co_ord.x = ((_x << 2) & 0x3fc) | (_v & 0x3); co_ord.y = ((_y << 2) & 0x3fc) | ((_v & 0xc) >> 2);

- ret = kfifo_in(&tsi->fifo, &co_ord, sizeof(struct da9052_tsi_reg)); + input_report_abs(tsi->dev, ABS_X, co_ord.x); + input_report_abs(tsi->dev, ABS_Y, co_ord.y); + input_report_abs(tsi->dev, ABS_PRESSURE, 1023); + input_sync(tsi->dev);

return 0; } @@ -135,131 +160,10 @@ static irqreturn_t da9052_ts_datardy_irq(int irq, void *data) return IRQ_NONE; }

- return IRQ_HANDLED; -} - -/* -* Two FIFO are been used. FIFO1 is used for detecting pen up and -* FIFO2 for reporting pen down co-ordinate. -*/ -void da9052_ts_process_reg_data(struct da9052_tsi *tsi) -{ - struct da9052_tsi_reg tmp_raw_data; - u32 reg_data_cnt; - int ret; - - reg_data_cnt = kfifo_len(&tsi->fifo); - - while (reg_data_cnt-- > 0) { - ret = kfifo_out(&tsi->fifo, &tmp_raw_data, - sizeof(struct da9052_tsi_reg)); - if (ret < 0) - continue; - kfifo_in(&tsi->fifo_buf, &tmp_raw_data, - sizeof(struct da9052_tsi_reg)); - } - return; -} - -static void da9052_ts_report_penup(struct da9052_tsi *tsi) -{ - struct input_dev *ip_dev = tsi->dev; - struct da9052 *da9052 = tsi->da9052; - ssize_t ret; - - ret = da9052_ts_stop(tsi); - if (ret < 0) - return; - - da9052->events_mask |= DA9052_E_TSI_READY; - da9052->events_mask &= ~DA9052_E_PEN_DOWN; - - /* Mask TSI_READY event and unmask PEN_DOWN event*/ - ret = da9052_reg_update(da9052, DA9052_IRQ_MASK_B_REG, 0x40, 0x80); - if (ret < 0) - return; - - input_report_abs(ip_dev, BTN_TOUCH, 0); - input_sync(ip_dev); - - tsi->zero_data_cnt = 0; -} - -/* -* This function detects the pen up state using the kfifo len. -* If kfifo len is zero for some interval then pen up is reported. -* Else pen co-ordinate are reported. -*/ -static int da9052_ts_monitor_pen_state(void *data) -{ - struct da9052_tsi *tsi = (struct da9052_tsi *) data; - u32 data_cnt; - - set_freezable(); - - while (tsi->tsi_pen_state_thread.state == DA9052_ACTIVE) { - try_to_freeze(); - - set_current_state(TASK_INTERRUPTIBLE); - schedule_timeout(msecs_to_jiffies(10)); - - if (tsi->pen_state != DA9052_PEN_DOWN) - continue; - - data_cnt = kfifo_len(&tsi->fifo); - if (data_cnt < 0) - continue; - - da9052_ts_process_reg_data(tsi); - - if (data_cnt) - tsi->zero_data_cnt = 0; - else { - if ((++(tsi->zero_data_cnt)) > - tsi->valid_penup_count) { - tsi->pen_state = DA9052_PEN_UP; - da9052_ts_report_penup(tsi); - } - } - } - - complete_and_exit(&tsi->tsi_pen_state_thread.notifier, 0); - return 0; -} - -static int da9052_ts_process_thread(void *ptr) -{ - struct da9052_tsi_reg co_ord; - int cnt = 0, ret; - struct da9052_tsi *tsi = (struct da9052_tsi *)ptr; - - set_freezable(); - - while (tsi->tsi_filter_thread.state == DA9052_ACTIVE) { - - try_to_freeze(); - - set_current_state(TASK_INTERRUPTIBLE); - schedule_timeout(msecs_to_jiffies(10)); - cnt = kfifo_len(&tsi->fifo_buf); - if (cnt <= 0) - continue; - - ret = kfifo_out(&tsi->fifo_buf, &co_ord, - sizeof(struct da9052_tsi_reg)); - if (ret < 0) - continue; - - input_report_abs(tsi->dev, BTN_TOUCH, 1); - input_report_abs(tsi->dev, ABS_X, co_ord.x); - input_report_abs(tsi->dev, ABS_Y, co_ord.y); - input_sync(tsi->dev); - } - - tsi->tsi_filter_thread.thread_task = NULL; - complete_and_exit(&tsi->tsi_filter_thread.notifier, 0); + /* start polling for touch_det to detect release */ + schedule_delayed_work(&tsi->work, HZ / 50);

- return 0; + return IRQ_HANDLED; }

static int da9052_ts_configure_gpio(struct da9052 *da9052) @@ -296,16 +200,6 @@ static int __init da9052_ts_enable_device(struct da9052_tsi *tsi)

tsi->valid_penup_count = 5;

- init_completion(&tsi->tsi_pen_state_thread.notifier); - tsi->tsi_pen_state_thread.state = DA9052_ACTIVE; - tsi->tsi_pen_state_thread.pid = kernel_thread(da9052_ts_monitor_pen_state, tsi, - CLONE_KERNEL | SIGCHLD); - - init_completion(&tsi->tsi_filter_thread.notifier); - tsi->tsi_filter_thread.state = DA9052_ACTIVE; - tsi->tsi_filter_thread.pid = kernel_thread(da9052_ts_process_thread, tsi, - CLONE_KERNEL | SIGCHLD); - tsi->zero_data_cnt = 0;

/* Measure TSI sample every 1ms */ @@ -354,14 +248,6 @@ static s32 __devinit da9052_ts_probe(struct platform_device *pdev) goto err_mem; }

- ret = kfifo_alloc(&tsi->fifo, DA9052_TSI_FIFOSIZE, GFP_KERNEL); - if (ret < 0) - goto err_input; - - ret = kfifo_alloc(&tsi->fifo_buf, DA9052_TSI_FIFOSIZE, GFP_KERNEL); - if (ret < 0) - goto err_fifo; - tsi->da9052 = da9052; tsi->pen_up_detect_interval = 5; platform_set_drvdata(pdev, tsi); @@ -388,6 +274,8 @@ static s32 __devinit da9052_ts_probe(struct platform_device *pdev) if (ret) goto err_mem;

+ INIT_DELAYED_WORK(&tsi->work, da9052_work); + tsi->irq_pendwn = platform_get_irq_byname(pdev, "PENDWN"); ret = request_threaded_irq(tsi->da9052->irq_base + tsi->irq_pendwn, NULL, da9052_ts_pendwn_irq, @@ -397,7 +285,7 @@ static s32 __devinit da9052_ts_probe(struct platform_device *pdev) dev_err(tsi->da9052->dev, "Failed to register %s IRQ %d, error = %d\n", "PENDWN", tsi->da9052->irq_base + tsi->irq_pendwn, ret); - goto err_fifo_buf; + goto err_input; }

tsi->irq_datardy = platform_get_irq_byname(pdev, "TSIRDY"); @@ -409,19 +297,15 @@ static s32 __devinit da9052_ts_probe(struct platform_device *pdev) dev_err(tsi->da9052->dev, "Failed to register %s IRQ %d, error = %d\n", "TSIRDY", tsi->da9052->irq_base + tsi->irq_datardy, ret); - goto err_fifo_buf; + goto err_input; }

ret = da9052_ts_enable_device(tsi); if (ret < 0) - goto err_fifo_buf; + goto err_input;

return 0;

-err_fifo_buf: - kfifo_free(&tsi->fifo_buf); -err_fifo: - kfifo_free(&tsi->fifo); err_input: input_free_device(input_dev); err_mem: @@ -445,18 +329,11 @@ static int __devexit da9052_ts_remove(struct platform_device *pdev) free_irq(tsi->da9052->irq_base + tsi->irq_pendwn, NULL); free_irq(tsi->da9052->irq_base + tsi->irq_datardy, NULL);

- tsi->tsi_pen_state_thread.state = DA9052_INACTIVE; - wait_for_completion(&tsi->tsi_pen_state_thread.notifier); - - tsi->tsi_filter_thread.state = DA9052_INACTIVE; - wait_for_completion(&tsi->tsi_filter_thread.notifier); - + cancel_delayed_work(&tsi->work); input_unregister_device(tsi->dev);

platform_set_drvdata(pdev, NULL);

- kfifo_free(&tsi->fifo); - kfifo_free(&tsi->fifo_buf); kfree(tsi);

return 0;