target/linux/bcm27xx/patches-5.15/950-0662-drivers-bcm2835_unicam-Disable-trigger-mode-operatio.patch

   1 From 70198f4ed03a3df670d5e12ab78bb3c4c2520396 Mon Sep 17 00:00:00 2001
   2 From: Naushir Patuck <naush@raspberrypi.com>
   3 Date: Tue, 18 Jan 2022 13:13:14 +0000
   4 Subject: [PATCH] drivers: bcm2835_unicam: Disable trigger mode
   5  operation
   6
   7 On a Pi3 B/B+ platform the imx219 sensor frequently generates a single corrupt
   8 frame when the sensor first starts. This can either be a missing line, or
   9 invalid samples within the line. This only occurrs using the Unicam kernel
  10 driver.
  11
  12 Disabling trigger mode elimiates this corruption. Since trigger mode is a
  13 legacy feature copied from the firmware driver and not expected to be needed,
  14 remove it. Tested on the Raspberry Pi cameras and shows no ill effects.
  15
  16 Signed-off-by: Naushir Patuck <naush@raspberrypi.com>
  17 ---
  18  drivers/media/platform/bcm2835/bcm2835-unicam.c | 14 +-------------
  19  1 file changed, 1 insertion(+), 13 deletions(-)
  20
  21 --- a/drivers/media/platform/bcm2835/bcm2835-unicam.c
  22 +++ b/drivers/media/platform/bcm2835/bcm2835-unicam.c
  23 @@ -984,11 +984,6 @@ static irqreturn_t unicam_isr(int irq, v
  24                 }
  25         }
  26
  27 -       if (reg_read(unicam, UNICAM_ICTL) & UNICAM_FCM) {
  28 -               /* Switch out of trigger mode if selected */
  29 -               reg_write_field(unicam, UNICAM_ICTL, 1, UNICAM_TFC);
  30 -               reg_write_field(unicam, UNICAM_ICTL, 0, UNICAM_FCM);
  31 -       }
  32         return IRQ_HANDLED;
  33  }
  34
  35 @@ -2298,8 +2293,7 @@ static void unicam_start_rx(struct unica
  36
  37         reg_write_field(dev, UNICAM_ANA, 0, UNICAM_DDL);
  38
  39 -       /* Always start in trigger frame capture mode (UNICAM_FCM set) */
  40 -       val = UNICAM_FSIE | UNICAM_FEIE | UNICAM_FCM | UNICAM_IBOB;
  41 +       val = UNICAM_FSIE | UNICAM_FEIE | UNICAM_IBOB;
  42         set_field(&val, line_int_freq, UNICAM_LCIE_MASK);
  43         reg_write(dev, UNICAM_ICTL, val);
  44         reg_write(dev, UNICAM_STA, UNICAM_STA_MASK_ALL);
  45 @@ -2412,12 +2406,6 @@ static void unicam_start_rx(struct unica
  46         /* Load embedded data buffer pointers if needed */
  47         if (dev->node[METADATA_PAD].streaming && dev->sensor_embedded_data)
  48                 reg_write_field(dev, UNICAM_DCS, 1, UNICAM_LDP);
  49 -
  50 -       /*
  51 -        * Enable trigger only for the first frame to
  52 -        * sync correctly to the FS from the source.
  53 -        */
  54 -       reg_write_field(dev, UNICAM_ICTL, 1, UNICAM_TFC);
  55  }
  56
  57  static void unicam_disable(struct unicam_device *dev)