@@ -100,13 +100,15 @@
#define ISC_WB_O_RGR 0x00000060
/* ISC White Balance Offset for B, GB Register */
-#define ISC_WB_O_BGR 0x00000064
+#define ISC_WB_O_BGB 0x00000064
/* ISC White Balance Gain for R, GR Register */
#define ISC_WB_G_RGR 0x00000068
/* ISC White Balance Gain for B, GB Register */
-#define ISC_WB_G_BGR 0x0000006c
+#define ISC_WB_G_BGB 0x0000006c
+
+#define ISC_WB_O_ZERO_VAL (1 << 13)
/* ISC Color Filter Array Control Register */
#define ISC_CFA_CTRL 0x00000070
@@ -169,13 +169,17 @@ struct isc_ctrls {
u8 gamma_index;
u8 awb;
- u32 r_gain;
- u32 b_gain;
+ /* one for each component : GR, R, GB, B */
+ u32 gain[HIST_BAYER];
+ u32 offset[HIST_BAYER];
u32 hist_entry[HIST_ENTRIES];
u32 hist_count[HIST_BAYER];
u8 hist_id;
u8 hist_stat;
+#define HIST_MIN_INDEX 0
+#define HIST_MAX_INDEX 1
+ u32 hist_minmax[HIST_BAYER][2];
};
#define ISC_PIPE_LINE_NODE_NUM 11
@@ -209,6 +213,7 @@ struct isc_device {
struct work_struct awb_work;
struct mutex lock;
+ spinlock_t awb_lock;
struct regmap_field *pipeline[ISC_PIPE_LINE_NODE_NUM];
@@ -395,6 +400,40 @@ module_param(sensor_preferred, uint, 0644);
MODULE_PARM_DESC(sensor_preferred,
"Sensor is preferred to output the specified format (1-on 0-off), default 1");
+static inline void isc_update_awb_ctrls(struct isc_device *isc)
+{
+ struct isc_ctrls *ctrls = &isc->ctrls;
+
+ regmap_write(isc->regmap, ISC_WB_O_RGR,
+ (ISC_WB_O_ZERO_VAL - (ctrls->offset[ISC_HIS_CFG_MODE_R])) |
+ ((ISC_WB_O_ZERO_VAL - ctrls->offset[ISC_HIS_CFG_MODE_GR]) << 16));
+ regmap_write(isc->regmap, ISC_WB_O_BGB,
+ (ISC_WB_O_ZERO_VAL - (ctrls->offset[ISC_HIS_CFG_MODE_B])) |
+ ((ISC_WB_O_ZERO_VAL - ctrls->offset[ISC_HIS_CFG_MODE_GB]) << 16));
+ regmap_write(isc->regmap, ISC_WB_G_RGR,
+ ctrls->gain[ISC_HIS_CFG_MODE_R] |
+ (ctrls->gain[ISC_HIS_CFG_MODE_GR] << 16));
+ regmap_write(isc->regmap, ISC_WB_G_BGB,
+ ctrls->gain[ISC_HIS_CFG_MODE_B] |
+ (ctrls->gain[ISC_HIS_CFG_MODE_GB] << 16));
+}
+
+static inline void isc_reset_awb_ctrls(struct isc_device *isc)
+{
+ int c;
+
+ for (c = ISC_HIS_CFG_MODE_GR; c <= ISC_HIS_CFG_MODE_B; c++) {
+ /* gains have a fixed point at 9 decimals */
+ isc->ctrls.gain[c] = 1 << 9;
+ /* offsets are in 2's complements, the value
+ * will be substracted from ISC_WB_O_ZERO_VAL to obtain
+ * 2's complement of a value between 0 and
+ * ISC_WB_O_ZERO_VAL >> 1
+ */
+ isc->ctrls.offset[c] = ISC_WB_O_ZERO_VAL;
+ }
+}
+
static int isc_wait_clk_stable(struct clk_hw *hw)
{
struct isc_clk *isc_clk = to_isc_clk(hw);
@@ -775,7 +814,9 @@ static void isc_start_dma(struct isc_device *isc)
dctrl_dview = isc->config.dctrl_dview;
regmap_write(regmap, ISC_DCTRL, dctrl_dview | ISC_DCTRL_IE_IS);
+ spin_lock(&isc->awb_lock);
regmap_write(regmap, ISC_CTRLEN, ISC_CTRL_CAPTURE);
+ spin_unlock(&isc->awb_lock);
}
static void isc_set_pipeline(struct isc_device *isc, u32 pipeline)
@@ -797,11 +838,11 @@ static void isc_set_pipeline(struct isc_device *isc, u32 pipeline)
bay_cfg = isc->config.sd_format->cfa_baycfg;
+ if (!ctrls->awb)
+ isc_reset_awb_ctrls(isc);
+
regmap_write(regmap, ISC_WB_CFG, bay_cfg);
- regmap_write(regmap, ISC_WB_O_RGR, 0x0);
- regmap_write(regmap, ISC_WB_O_BGR, 0x0);
- regmap_write(regmap, ISC_WB_G_RGR, ctrls->r_gain | (0x1 << 25));
- regmap_write(regmap, ISC_WB_G_BGR, ctrls->b_gain | (0x1 << 25));
+ isc_update_awb_ctrls(isc);
regmap_write(regmap, ISC_CFA_CFG, bay_cfg | ISC_CFA_CFG_EITPOL);
@@ -851,13 +892,13 @@ static void isc_set_histogram(struct isc_device *isc, bool enable)
if (enable) {
regmap_write(regmap, ISC_HIS_CFG,
- ISC_HIS_CFG_MODE_R |
+ ISC_HIS_CFG_MODE_GR |
(isc->config.sd_format->cfa_baycfg
<< ISC_HIS_CFG_BAYSEL_SHIFT) |
ISC_HIS_CFG_RAR);
regmap_write(regmap, ISC_HIS_CTRL, ISC_HIS_CTRL_EN);
regmap_write(regmap, ISC_INTEN, ISC_INT_HISDONE);
- ctrls->hist_id = ISC_HIS_CFG_MODE_R;
+ ctrls->hist_id = ISC_HIS_CFG_MODE_GR;
isc_update_profile(isc);
regmap_write(regmap, ISC_CTRLEN, ISC_CTRL_HISREQ);
@@ -900,7 +941,7 @@ static int isc_configure(struct isc_device *isc)
isc_set_pipeline(isc, pipeline);
/*
- * The current implemented histogram is available for RAW R, B, GB
+ * The current implemented histogram is available for RAW R, B, GB, GR
* channels. We need to check if sensor is outputting RAW BAYER
*/
if (isc->ctrls.awb &&
@@ -1475,6 +1516,12 @@ static int isc_set_fmt(struct isc_device *isc, struct v4l2_format *f)
return ret;
isc->fmt = *f;
+
+ if (isc->try_config.sd_format && isc->config.sd_format &&
+ isc->try_config.sd_format != isc->config.sd_format) {
+ isc->ctrls.hist_stat = HIST_INIT;
+ isc_reset_awb_ctrls(isc);
+ }
/* make the try configuration active */
isc->config = isc->try_config;
@@ -1758,7 +1805,7 @@ static irqreturn_t isc_interrupt(int irq, void *dev_id)
return ret;
}
-static void isc_hist_count(struct isc_device *isc)
+static void isc_hist_count(struct isc_device *isc, u32 *min, u32 *max)
{
struct regmap *regmap = isc->regmap;
struct isc_ctrls *ctrls = &isc->ctrls;
@@ -1766,25 +1813,99 @@ static void isc_hist_count(struct isc_device *isc)
u32 *hist_entry = &ctrls->hist_entry[0];
u32 i;
+ *min = 0;
+ *max = HIST_ENTRIES;
+
regmap_bulk_read(regmap, ISC_HIS_ENTRY, hist_entry, HIST_ENTRIES);
*hist_count = 0;
- for (i = 0; i < HIST_ENTRIES; i++)
+ /*
+ * we deliberately ignore the end of the histogram,
+ * the most white pixels
+ */
+ for (i = 1; i < HIST_ENTRIES; i++) {
+ if (*hist_entry && !*min)
+ *min = i;
+ if (*hist_entry)
+ *max = i;
*hist_count += i * (*hist_entry++);
+ }
+
+ if (!*min)
+ *min = 1;
}
static void isc_wb_update(struct isc_ctrls *ctrls)
{
u32 *hist_count = &ctrls->hist_count[0];
- u64 g_count = (u64)hist_count[ISC_HIS_CFG_MODE_GB] << 9;
- u32 hist_r = hist_count[ISC_HIS_CFG_MODE_R];
- u32 hist_b = hist_count[ISC_HIS_CFG_MODE_B];
+ u32 c, offset[4];
+ u64 avg = 0;
+ /* We compute two gains, stretch gain and grey world gain */
+ u32 s_gain[4], gw_gain[4];
- if (hist_r)
- ctrls->r_gain = div_u64(g_count, hist_r);
+ /*
+ * According to Grey World, we need to set gains for R/B to normalize
+ * them towards the green channel.
+ * Thus we want to keep Green as fixed and adjust only Red/Blue
+ * Compute the average of the both green channels first
+ */
+ avg = (u64)hist_count[ISC_HIS_CFG_MODE_GR] +
+ (u64)hist_count[ISC_HIS_CFG_MODE_GB];
+ avg >>= 1;
+
+ /* Green histogram is null, nothing to do */
+ if (!avg)
+ return;
- if (hist_b)
- ctrls->b_gain = div_u64(g_count, hist_b);
+ for (c = ISC_HIS_CFG_MODE_GR; c <= ISC_HIS_CFG_MODE_B; c++) {
+ /*
+ * the color offset is the minimum value of the histogram.
+ * we stretch this color to the full range by substracting
+ * this value from the color component.
+ */
+ offset[c] = ctrls->hist_minmax[c][HIST_MIN_INDEX];
+ /*
+ * The offset is always at least 1. If the offset is 1, we do
+ * not need to adjust it, so our result must be zero.
+ * the offset is computed in a histogram on 9 bits (0..512)
+ * but the offset in register is based on
+ * 12 bits pipeline (0..4096).
+ * we need to shift with the 3 bits that the histogram is
+ * ignoring
+ */
+ ctrls->offset[c] = (offset[c] - 1) << 3;
+
+ /* the offset is then taken and converted to 2's complements */
+ if (!ctrls->offset[c])
+ ctrls->offset[c] = ISC_WB_O_ZERO_VAL;
+
+ /*
+ * the stretch gain is the total number of histogram bins
+ * divided by the actual range of color component (Max - Min)
+ * If we compute gain like this, the actual color component
+ * will be stretched to the full histogram.
+ * We need to shift 9 bits for precision, we have 9 bits for
+ * decimals
+ */
+ s_gain[c] = (HIST_ENTRIES << 9) /
+ (ctrls->hist_minmax[c][HIST_MAX_INDEX] -
+ ctrls->hist_minmax[c][HIST_MIN_INDEX] + 1);
+
+ /*
+ * Now we have to compute the gain w.r.t. the average.
+ * Add/lose gain to the component towards the average.
+ * If it happens that the component is zero, use the
+ * fixed point value : 1.0 gain.
+ */
+ if (hist_count[c])
+ gw_gain[c] = div_u64(avg << 9, hist_count[c]);
+ else
+ gw_gain[c] = 1 << 9;
+
+ /* multiply both gains and adjust for decimals */
+ ctrls->gain[c] = s_gain[c] * gw_gain[c];
+ ctrls->gain[c] >>= 9;
+ }
}
static void isc_awb_work(struct work_struct *w)
@@ -1795,27 +1916,56 @@ static void isc_awb_work(struct work_struct *w)
struct isc_ctrls *ctrls = &isc->ctrls;
u32 hist_id = ctrls->hist_id;
u32 baysel;
+ unsigned long flags;
+ u32 min, max;
+
+ /* streaming is not active anymore */
+ if (isc->stop)
+ return;
if (ctrls->hist_stat != HIST_ENABLED)
return;
- isc_hist_count(isc);
+ isc_hist_count(isc, &min, &max);
+ ctrls->hist_minmax[hist_id][HIST_MIN_INDEX] = min;
+ ctrls->hist_minmax[hist_id][HIST_MAX_INDEX] = max;
if (hist_id != ISC_HIS_CFG_MODE_B) {
hist_id++;
} else {
isc_wb_update(ctrls);
- hist_id = ISC_HIS_CFG_MODE_R;
+ hist_id = ISC_HIS_CFG_MODE_GR;
}
ctrls->hist_id = hist_id;
baysel = isc->config.sd_format->cfa_baycfg << ISC_HIS_CFG_BAYSEL_SHIFT;
+ /* if no more auto white balance, reset controls. */
+ if (!ctrls->awb)
+ isc_reset_awb_ctrls(isc);
+
pm_runtime_get_sync(isc->dev);
+ /*
+ * only update if we have all the required histograms and controls
+ * if awb has been disabled, we need to reset registers as well.
+ */
+ if (hist_id == ISC_HIS_CFG_MODE_GR || !ctrls->awb) {
+ /*
+ * It may happen that DMA Done IRQ will trigger while we are
+ * updating white balance registers here.
+ * In that case, only parts of the controls have been updated.
+ * We can avoid that by locking the section.
+ */
+ spin_lock_irqsave(&isc->awb_lock, flags);
+ isc_update_awb_ctrls(isc);
+ spin_unlock_irqrestore(&isc->awb_lock, flags);
+ }
regmap_write(regmap, ISC_HIS_CFG, hist_id | baysel | ISC_HIS_CFG_RAR);
isc_update_profile(isc);
- regmap_write(regmap, ISC_CTRLEN, ISC_CTRL_HISREQ);
+ /* if awb has been disabled, we don't need to start another histogram */
+ if (ctrls->awb)
+ regmap_write(regmap, ISC_CTRLEN, ISC_CTRL_HISREQ);
pm_runtime_put_sync(isc->dev);
}
@@ -1839,8 +1989,7 @@ static int isc_s_ctrl(struct v4l2_ctrl *ctrl)
case V4L2_CID_AUTO_WHITE_BALANCE:
ctrls->awb = ctrl->val;
if (ctrls->hist_stat != HIST_ENABLED) {
- ctrls->r_gain = 0x1 << 9;
- ctrls->b_gain = 0x1 << 9;
+ isc_reset_awb_ctrls(isc);
}
break;
default:
@@ -1862,11 +2011,15 @@ static int isc_ctrl_init(struct isc_device *isc)
int ret;
ctrls->hist_stat = HIST_INIT;
+ isc_reset_awb_ctrls(isc);
ret = v4l2_ctrl_handler_init(hdl, 4);
if (ret < 0)
return ret;
+ ctrls->brightness = 0;
+ ctrls->contrast = 256;
+
v4l2_ctrl_new_std(hdl, ops, V4L2_CID_BRIGHTNESS, -1024, 1023, 1, 0);
v4l2_ctrl_new_std(hdl, ops, V4L2_CID_CONTRAST, -2048, 2047, 1, 256);
v4l2_ctrl_new_std(hdl, ops, V4L2_CID_GAMMA, 0, GAMMA_MAX, 1, 2);
@@ -2034,6 +2187,7 @@ static int isc_async_complete(struct v4l2_async_notifier *notifier)
/* Init video dma queues */
INIT_LIST_HEAD(&isc->dma_queue);
spin_lock_init(&isc->dma_queue_lock);
+ spin_lock_init(&isc->awb_lock);
ret = isc_formats_init(isc);
if (ret < 0) {