input/cyttsp: optimize msleeps in device initialization path

BZ: 4982

Optimize generous msleeps in the device initialization code
to reduce the total cyttsp boot time from 2839065 usecs to 249755 usecs.
This saves around ~2.5s of total platform boot time

Change-Id: I96bc9668a930251a5cbec5643d705b4b2aff6f7f
Signed-off-by: Sundar Iyer <sundar.iyer@intel.com>

diff --git a/drivers/input/touchscreen/cyttsp_core.c b/drivers/input/touchscreen/cyttsp_core.c
index 4d14b61..47d8e18 100644 (file)
--- a/drivers/input/touchscreen/cyttsp_core.c
+++ b/drivers/input/touchscreen/cyttsp_core.c
@@ -1093,15 +1093,20 @@ static int cyttsp_exit_bl_mode(struct cyttsp *ts)
 
        retval = ttsp_write_block_data(ts, CY_REG_BASE, sizeof(bl_cmd),
                        (void *)bl_cmd);
+
+       /* data sheet Table 10-6 for delays during mode switches */
+       msleep(CY_DELAY_SYSINFO);
+
        if (retval < 0) {
                dev_err(ts->pdev, "%s: failed writing block data, err:%d\n",
                        __func__, retval);
                goto fail;
        }
+
        do {
-               msleep(500);
                cyttsp_load_bl_regs(ts);
        } while (GET_BOOTLOADERMODE(ts->bl_data.bl_status) && tries++ < 10);
+
        return 0;
 fail:
        return retval;
@@ -1115,8 +1120,10 @@ static int cyttsp_set_sysinfo_mode(struct cyttsp *ts)
        dev_dbg(ts->pdev, "%s: enter\n", __func__);
 
        retval = ttsp_write_block_data(ts, CY_REG_BASE, sizeof(cmd), &cmd);
+
        /* wait for TTSP Device to complete switch to SysInfo mode */
-       msleep(500);
+       msleep(CY_DELAY_SYSINFO);
+
        if (retval < 0) {
                dev_err(ts->pdev, "%s: Failed writing block data, err:%d\n",
                        __func__, retval);
@@ -1167,13 +1174,16 @@ static int cyttsp_set_operational_mode(struct cyttsp *ts)
        dev_dbg(ts->pdev, "%s: enter\n", __func__);
 
        retval = ttsp_write_block_data(ts, CY_REG_BASE, sizeof(cmd), &cmd);
+
+       /* data sheet Table 10-6 for delays during mode switches */
+       msleep(CY_DELAY_SYSINFO);
+
        if (retval < 0) {
                dev_err(ts->pdev, "%s: Failed writing block data, err:%d\n",
                        __func__, retval);
                return retval;
        }
-       /* wait for TTSP Device to complete switch to Operational mode */
-       msleep(500);
+
        return 0;
 }
 
@@ -1184,17 +1194,24 @@ static int cyttsp_soft_reset(struct cyttsp *ts)
        u8 cmd = CY_SOFT_RESET_MODE;
 
        dev_dbg(ts->pdev, "%s: enter\n", __func__);
+
        /* reset TTSP Device back to bootloader mode */
        retval = ttsp_write_block_data(ts, CY_REG_BASE, sizeof(cmd), &cmd);
+
        /* wait for TTSP Device to complete reset back to bootloader */
        tries = 0;
-       msleep(200);
+
+       /* data sheet Table 10-6 covers the time taken from power on to
+        * bootloader being ready
+        */
+       msleep(CY_DELAY_SYSINFO);
+
        do {
-               msleep(100);
                cyttsp_load_bl_regs(ts);
        } while (ts->bl_data.bl_status != 0x10 &&
                 ts->bl_data.bl_status != 0x11 &&
                 tries++ < 100);
+
        if (tries >= 100)
                dev_err(ts->pdev, "%s: bootlodader not ready, status 0x%02x\n",
                        __func__, ts->bl_data.bl_status);
@@ -1208,13 +1225,14 @@ static int cyttsp_power_on(struct cyttsp *ts)
        int tries = 0;
 
        dev_dbg(ts->pdev, "%s: enter\n", __func__);
+
        /* check if the TTSP device has a bootloader installed */
        retval = cyttsp_soft_reset(ts);
        if (retval < 0)
                goto bypass;
 
+       /* the boot loader is already installed */
        do {
-               msleep(500);
                retval = cyttsp_load_bl_regs(ts);
        } while (!GET_BOOTLOADERMODE(ts->bl_data.bl_status) &&
                !(GET_HSTMODE(ts->bl_data.bl_file) == CY_OPERATE_MODE) &&
@@ -1271,9 +1289,11 @@ static int cyttsp_power_on(struct cyttsp *ts)
 
        cmd = CY_OPERATE_MODE;
        retval = ttsp_write_block_data(ts, CY_REG_BASE, sizeof(cmd), &cmd);
+
        /* wait for TTSP Device to complete switch to */
        /* Operational mode */
-       msleep(1000);
+       msleep(CY_DELAY_SYSINFO);
+
        /* init gesture setup */
        if (retval < 0)
                goto bypass;