[PATCH 0/4] Removing dead code

[PATCH 0/4] Removing dead code

[Christian Dietrich]

Hi all!
       
        As part of the VAMOS[0] research project at the University of
Erlangen we are looking at multiple integrity errors in linux'
configuration system.

        I've been running a check on the drivers/media sourcetree for
config Items not defined in Kconfig and found 4 such cases. Sourcecode
blocks depending on these Items are not reachable from a vanilla
kernel -- dead code. I've seen such dead blocks made on purpose
e.g. while integrating new features into the kernel but generally
they're just useless.

        There were also CONFIG_ options set within a source file. This
created code blocks which were always selected and compiled.

        Each of the patches in this patchset removes on such dead
config Item, I'd be glad if you consider applying them. I've been
doing deeper analysis of such issues before and can do so again but
I'm not so sure they were fastly usefull.

        I build the patches against a vanilla kernel in order to
try if the kernel compiles with this patches

        Please keep me informed of this patch getting confirmed /
merged so we can keep track of it.

Regards

        Christian Dietrich

[0] http://vamos1.informatik.uni-erlangen.de/

Christian Dietrich (4):
  drivers/media/dvb: Remove dead Configs
  drivers/media/dvb: Remove undead configs
  drivers/media/video: Remove dead CONFIG_FB_OMAP2_FORCE_AUTO_UPDATE
  drivers/media/video: Remove dead CONFIG_OLPC_X0_1

 drivers/media/dvb/frontends/dib0090.c |  126 ---------------------------------
 drivers/media/video/omap/omap_vout.c  |    8 --
 drivers/media/video/ov7670.c          |   37 ----------
 3 files changed, 0 insertions(+), 171 deletions(-)

[PATCH 1/4] drivers/media/dvb: Remove dead Configs

[Christian Dietrich]

Following flags were checked, but never set anywhere, therefore
removing all references from the source code:

CONFIG_BAND_SBAND
CONFIG_BAND_LBAND
CONFIG_STANDARD_DAB
CONFIG_STANDARD_DVBT
CONFIG_TUNER_DIB0090_P1B_SUPPORT
CONFIG_TUNER_DIB0090_CPTURIM_MEMORY
FIREFLY_FIRMWARE

Signed-off-by: Christian Dietrich <qy03fugy@stud.informatik.uni-erlangen.de>
---
 drivers/media/dvb/frontends/dib0090.c |   84 ---------------------------------
 1 files changed, 0 insertions(+), 84 deletions(-)

diff --git a/drivers/media/dvb/frontends/dib0090.c b/drivers/media/dvb/frontends/dib0090.c
index 65240b7..c54ce31 100644
--- a/drivers/media/dvb/frontends/dib0090.c
+++ b/drivers/media/dvb/frontends/dib0090.c
@@ -190,12 +190,6 @@ static u16 dib0090_identify(struct dvb_frontend *fe)
 
 	v = dib0090_read_reg(state, 0x1a);
 
-#ifdef FIRMWARE_FIREFLY
-	/* pll is not locked locked */
-	if (!(v & 0x800))
-		dprintk("FE%d : Identification : pll is not yet locked", fe->id);
-#endif
-
 	/* without PLL lock info */
 	v &= 0x3ff;
 	dprintk("P/V: %04x:", v);
@@ -223,13 +217,8 @@ static u16 dib0090_identify(struct dvb_frontend *fe)
 	else if ((v & 0x1f) == 0x1)
 		dprintk("FE%d : P1C detected", fe->id);
 	else if ((v & 0x1f) == 0x0) {
-#ifdef CONFIG_TUNER_DIB0090_P1B_SUPPORT
-		dprintk("FE%d : P1-A/B detected: using previous driver - support will be removed soon", fe->id);
-		dib0090_p1b_register(fe);
-#else
 		dprintk("FE%d : P1-A/B detected: driver is deactivated - not available", fe->id);
 		return 0xff;
-#endif
 	}
 
 	return v;
@@ -424,12 +413,10 @@ static void dib0090_wbd_target(struct dib0090_state *state, u32 rf)
 
 	if (state->current_band == BAND_VHF)
 		offset = 650;
-#ifndef FIRMWARE_FIREFLY
 	if (state->current_band == BAND_VHF)
 		offset = state->config->wbd_vhf_offset;
 	if (state->current_band == BAND_CBAND)
 		offset = state->config->wbd_cband_offset;
-#endif
 
 	state->wbd_target = dib0090_wbd_to_db(state, state->wbd_offset + offset);
 	dprintk("wbd-target: %d dB", (u32) state->wbd_target);
@@ -589,12 +576,6 @@ void dib0090_pwm_gain_reset(struct dvb_frontend *fe)
 	/* reset the AGC */
 
 	if (state->config->use_pwm_agc) {
-#ifdef CONFIG_BAND_SBAND
-		if (state->current_band == BAND_SBAND) {
-			dib0090_set_rframp_pwm(state, rf_ramp_pwm_sband);
-			dib0090_set_bbramp_pwm(state, bb_ramp_pwm_boost);
-		} else
-#endif
 #ifdef CONFIG_BAND_CBAND
 		if (state->current_band == BAND_CBAND) {
 			dib0090_set_rframp_pwm(state, rf_ramp_pwm_cband);
@@ -636,12 +617,6 @@ int dib0090_gain_control(struct dvb_frontend *fe)
 		state->agc_freeze = 0;
 		dib0090_write_reg(state, 0x04, 0x0);
 
-#ifdef CONFIG_BAND_SBAND
-		if (state->current_band == BAND_SBAND) {
-			dib0090_set_rframp(state, rf_ramp_sband);
-			dib0090_set_bbramp(state, bb_ramp_boost);
-		} else
-#endif
 #ifdef CONFIG_BAND_VHF
 		if (state->current_band == BAND_VHF) {
 			dib0090_set_rframp(state, rf_ramp_vhf);
@@ -698,15 +673,6 @@ int dib0090_gain_control(struct dvb_frontend *fe)
 			adc = (adc * ((s32) 355774) + (((s32) 1) << 20)) >> 21;	/* included in [0:-700] */
 
 			adc_error = (s16) (((s32) ADC_TARGET) - adc);
-#ifdef CONFIG_STANDARD_DAB
-			if (state->fe->dtv_property_cache.delivery_system == STANDARD_DAB)
-				adc_error += 130;
-#endif
-#ifdef CONFIG_STANDARD_DVBT
-			if (state->fe->dtv_property_cache.delivery_system == STANDARD_DVBT &&
-			    (state->fe->dtv_property_cache.modulation == QAM_64 || state->fe->dtv_property_cache.modulation == QAM_16))
-				adc_error += 60;
-#endif
 #ifdef CONFIG_SYS_ISDBT
 			if ((state->fe->dtv_property_cache.delivery_system == SYS_ISDBT) && (((state->fe->dtv_property_cache.layer[0].segment_count >
 											       0)
@@ -738,13 +704,6 @@ int dib0090_gain_control(struct dvb_frontend *fe)
 
 			if (*tune_state == CT_AGC_STEP_1) {	/* quickly go to the correct range of the ADC power */
 				if (ABS(adc_error) < 50 || state->agc_step++ > 5) {
-
-#ifdef CONFIG_STANDARD_DAB
-					if (state->fe->dtv_property_cache.delivery_system == STANDARD_DAB) {
-						dib0090_write_reg(state, 0x02, (1 << 15) | (15 << 11) | (31 << 6) | (63));	/* cap value = 63 : narrow BB filter : Fc = 1.8MHz */
-						dib0090_write_reg(state, 0x04, 0x0);
-					} else
-#endif
 					{
 						dib0090_write_reg(state, 0x02, (1 << 15) | (3 << 11) | (6 << 6) | (32));
 						dib0090_write_reg(state, 0x04, 0x01);	/*0 = 1KHz ; 1 = 150Hz ; 2 = 50Hz ; 3 = 50KHz ; 4 = servo fast */
@@ -860,11 +819,6 @@ static int dib0090_reset(struct dvb_frontend *fe)
 		dib0090_set_EFUSE(state);
 #endif
 
-#ifdef CONFIG_TUNER_DIB0090_P1B_SUPPORT
-	if (!(state->revision & 0x1))	/* it is P1B - reset is already done */
-		return 0;
-#endif
-
 	/* Upload the default values */
 	n = (u16 *) dib0090_defaults;
 	l = pgm_read_word(n++);
@@ -1117,12 +1071,6 @@ static const struct dib0090_pll dib0090_pll_table[] = {
 	{700000, 0, 2, 4, 4},
 	{860000, 1, 2, 4, 4},
 #endif
-#ifdef CONFIG_BAND_LBAND
-	{1800000, 1, 0, 2, 4},
-#endif
-#ifdef CONFIG_BAND_SBAND
-	{2900000, 0, 14, 1, 4},
-#endif
 };
 
 static const struct dib0090_tuning dib0090_tuning_table_fm_vhf_on_cband[] = {
@@ -1140,15 +1088,6 @@ static const struct dib0090_tuning dib0090_tuning_table_fm_vhf_on_cband[] = {
 	{850000, 2, 6, 15, 0x300, 0x1d12, 0xb9ce, EN_UHF},
 	{900000, 2, 7, 15, 0x300, 0x1d12, 0xb9ce, EN_UHF},
 #endif
-#ifdef CONFIG_BAND_LBAND
-	{1500000, 4, 0, 20, 0x300, 0x1912, 0x82c9, EN_LBD},
-	{1600000, 4, 1, 20, 0x300, 0x1912, 0x82c9, EN_LBD},
-	{1800000, 4, 3, 20, 0x300, 0x1912, 0x82c9, EN_LBD},
-#endif
-#ifdef CONFIG_BAND_SBAND
-	{2300000, 1, 4, 20, 0x300, 0x2d2A, 0x82c7, EN_SBD},
-	{2900000, 1, 7, 20, 0x280, 0x2deb, 0x8347, EN_SBD},
-#endif
 };
 
 static const struct dib0090_tuning dib0090_tuning_table[] = {
@@ -1169,15 +1108,6 @@ static const struct dib0090_tuning dib0090_tuning_table[] = {
 	{850000, 2, 6, 15, 0x300, 0x1d12, 0xb9ce, EN_UHF},
 	{900000, 2, 7, 15, 0x300, 0x1d12, 0xb9ce, EN_UHF},
 #endif
-#ifdef CONFIG_BAND_LBAND
-	{1500000, 4, 0, 20, 0x300, 0x1912, 0x82c9, EN_LBD},
-	{1600000, 4, 1, 20, 0x300, 0x1912, 0x82c9, EN_LBD},
-	{1800000, 4, 3, 20, 0x300, 0x1912, 0x82c9, EN_LBD},
-#endif
-#ifdef CONFIG_BAND_SBAND
-	{2300000, 1, 4, 20, 0x300, 0x2d2A, 0x82c7, EN_SBD},
-	{2900000, 1, 7, 20, 0x280, 0x2deb, 0x8347, EN_SBD},
-#endif
 };
 
 #define WBD     0x781		/* 1 1 1 1 0000 0 0 1 */
@@ -1295,10 +1225,6 @@ static int dib0090_tune(struct dvb_frontend *fe)
 					lo6 |= (1 << 2) | 1;
 				Den = 255;
 			}
-#ifdef CONFIG_BAND_SBAND
-			if (state->current_band == BAND_SBAND)
-				lo6 &= 0xfffb;
-#endif
 
 			dib0090_write_reg(state, 0x15, (u16) FBDiv);
 
@@ -1377,10 +1303,6 @@ static int dib0090_tune(struct dvb_frontend *fe)
 		/*write the final cptrim config */
 		dib0090_write_reg(state, 0x18, lo4 | state->fcaptrim);
 
-#ifdef CONFIG_TUNER_DIB0090_CAPTRIM_MEMORY
-		state->memory[state->memory_index].cap = state->fcaptrim;
-#endif
-
 		*tune_state = CT_TUNER_STEP_4;
 	} else if (*tune_state == CT_TUNER_STEP_4) {
 		dib0090_write_reg(state, 0x1e, 0x07ff);
@@ -1396,12 +1318,6 @@ static int dib0090_tune(struct dvb_frontend *fe)
 
 		c = 4;
 		i = 3;
-#if defined(CONFIG_BAND_LBAND) || defined(CONFIG_BAND_SBAND)
-		if ((state->current_band == BAND_LBAND) || (state->current_band == BAND_SBAND)) {
-			c = 2;
-			i = 2;
-		}
-#endif
 		dib0090_write_reg(state, 0x10, (c << 13) | (i << 11) | (WBD
 #ifdef CONFIG_DIB0090_USE_PWM_AGC
 									| (state->config->use_pwm_agc << 1)
-- 
1.7.0.4

[PATCH 2/4] drivers/media/dvb: Remove undead configs

[Christian Dietrich]

The following CONFIG_ options are set within the C File, so the blocks
will always be selected. For the matter of readability the ifdefs are
not nesseccary:

CONFIG_BAND_CBAND
CONFIG_BAND_UHF
CONFIG_BAND_VHF
CONFIG_DIB0090_USE_PWM_AGC
CONFIG_SYS_ISDBT

Signed-off-by: Christian Dietrich <qy03fugy@stud.informatik.uni-erlangen.de>
---
 drivers/media/dvb/frontends/dib0090.c |   42 ---------------------------------
 1 files changed, 0 insertions(+), 42 deletions(-)

diff --git a/drivers/media/dvb/frontends/dib0090.c b/drivers/media/dvb/frontends/dib0090.c
index c54ce31..007878e 100644
--- a/drivers/media/dvb/frontends/dib0090.c
+++ b/drivers/media/dvb/frontends/dib0090.c
@@ -45,12 +45,6 @@ MODULE_PARM_DESC(debug, "turn on debugging (default: 0)");
 	} \
 } while (0)
 
-#define CONFIG_SYS_ISDBT
-#define CONFIG_BAND_CBAND
-#define CONFIG_BAND_VHF
-#define CONFIG_BAND_UHF
-#define CONFIG_DIB0090_USE_PWM_AGC
-
 #define EN_LNA0      0x8000
 #define EN_LNA1      0x4000
 #define EN_LNA2      0x2000
@@ -576,18 +570,14 @@ void dib0090_pwm_gain_reset(struct dvb_frontend *fe)
 	/* reset the AGC */
 
 	if (state->config->use_pwm_agc) {
-#ifdef CONFIG_BAND_CBAND
 		if (state->current_band == BAND_CBAND) {
 			dib0090_set_rframp_pwm(state, rf_ramp_pwm_cband);
 			dib0090_set_bbramp_pwm(state, bb_ramp_pwm_normal);
 		} else
-#endif
-#ifdef CONFIG_BAND_VHF
 		if (state->current_band == BAND_VHF) {
 			dib0090_set_rframp_pwm(state, rf_ramp_pwm_vhf);
 			dib0090_set_bbramp_pwm(state, bb_ramp_pwm_normal);
 		} else
-#endif
 		{
 			dib0090_set_rframp_pwm(state, rf_ramp_pwm_uhf);
 			dib0090_set_bbramp_pwm(state, bb_ramp_pwm_normal);
@@ -617,18 +607,14 @@ int dib0090_gain_control(struct dvb_frontend *fe)
 		state->agc_freeze = 0;
 		dib0090_write_reg(state, 0x04, 0x0);
 
-#ifdef CONFIG_BAND_VHF
 		if (state->current_band == BAND_VHF) {
 			dib0090_set_rframp(state, rf_ramp_vhf);
 			dib0090_set_bbramp(state, bb_ramp_boost);
 		} else
-#endif
-#ifdef CONFIG_BAND_CBAND
 		if (state->current_band == BAND_CBAND) {
 			dib0090_set_rframp(state, rf_ramp_cband);
 			dib0090_set_bbramp(state, bb_ramp_boost);
 		} else
-#endif
 		{
 			dib0090_set_rframp(state, rf_ramp_uhf);
 			dib0090_set_bbramp(state, bb_ramp_boost);
@@ -655,14 +641,12 @@ int dib0090_gain_control(struct dvb_frontend *fe)
 
 		if (*tune_state == CT_AGC_STEP_0) {
 			if (wbd_error < 0 && state->rf_gain_limit > 0) {
-#ifdef CONFIG_BAND_CBAND
 				/* in case of CBAND tune reduce first the lt_gain2 before adjusting the RF gain */
 				u8 ltg2 = (state->rf_lt_def >> 10) & 0x7;
 				if (state->current_band == BAND_CBAND && ltg2) {
 					ltg2 >>= 1;
 					state->rf_lt_def &= ltg2 << 10;	/* reduce in 3 steps from 7 to 0 */
 				}
-#endif
 			} else {
 				state->agc_step = 0;
 				*tune_state = CT_AGC_STEP_1;
@@ -673,7 +657,6 @@ int dib0090_gain_control(struct dvb_frontend *fe)
 			adc = (adc * ((s32) 355774) + (((s32) 1) << 20)) >> 21;	/* included in [0:-700] */
 
 			adc_error = (s16) (((s32) ADC_TARGET) - adc);
-#ifdef CONFIG_SYS_ISDBT
 			if ((state->fe->dtv_property_cache.delivery_system == SYS_ISDBT) && (((state->fe->dtv_property_cache.layer[0].segment_count >
 											       0)
 											      &&
@@ -700,7 +683,6 @@ int dib0090_gain_control(struct dvb_frontend *fe)
 			    )
 			    )
 				adc_error += 60;
-#endif
 
 			if (*tune_state == CT_AGC_STEP_1) {	/* quickly go to the correct range of the ADC power */
 				if (ABS(adc_error) < 50 || state->agc_step++ > 5) {
@@ -1049,7 +1031,6 @@ static void dib0090_set_bandwidth(struct dib0090_state *state)
 }
 
 static const struct dib0090_pll dib0090_pll_table[] = {
-#ifdef CONFIG_BAND_CBAND
 	{56000, 0, 9, 48, 6},
 	{70000, 1, 9, 48, 6},
 	{87000, 0, 8, 32, 4},
@@ -1057,57 +1038,40 @@ static const struct dib0090_pll dib0090_pll_table[] = {
 	{115000, 0, 7, 24, 6},
 	{140000, 1, 7, 24, 6},
 	{170000, 0, 6, 16, 4},
-#endif
-#ifdef CONFIG_BAND_VHF
 	{200000, 1, 6, 16, 4},
 	{230000, 0, 5, 12, 6},
 	{280000, 1, 5, 12, 6},
 	{340000, 0, 4, 8, 4},
 	{380000, 1, 4, 8, 4},
 	{450000, 0, 3, 6, 6},
-#endif
-#ifdef CONFIG_BAND_UHF
 	{580000, 1, 3, 6, 6},
 	{700000, 0, 2, 4, 4},
 	{860000, 1, 2, 4, 4},
-#endif
 };
 
 static const struct dib0090_tuning dib0090_tuning_table_fm_vhf_on_cband[] = {
-
-#ifdef CONFIG_BAND_CBAND
 	{184000, 4, 1, 15, 0x280, 0x2912, 0xb94e, EN_CAB},
 	{227000, 4, 3, 15, 0x280, 0x2912, 0xb94e, EN_CAB},
 	{380000, 4, 7, 15, 0x280, 0x2912, 0xb94e, EN_CAB},
-#endif
-#ifdef CONFIG_BAND_UHF
 	{520000, 2, 0, 15, 0x300, 0x1d12, 0xb9ce, EN_UHF},
 	{550000, 2, 2, 15, 0x300, 0x1d12, 0xb9ce, EN_UHF},
 	{650000, 2, 3, 15, 0x300, 0x1d12, 0xb9ce, EN_UHF},
 	{750000, 2, 5, 15, 0x300, 0x1d12, 0xb9ce, EN_UHF},
 	{850000, 2, 6, 15, 0x300, 0x1d12, 0xb9ce, EN_UHF},
 	{900000, 2, 7, 15, 0x300, 0x1d12, 0xb9ce, EN_UHF},
-#endif
 };
 
 static const struct dib0090_tuning dib0090_tuning_table[] = {
-
-#ifdef CONFIG_BAND_CBAND
 	{170000, 4, 1, 15, 0x280, 0x2912, 0xb94e, EN_CAB},
-#endif
-#ifdef CONFIG_BAND_VHF
 	{184000, 1, 1, 15, 0x300, 0x4d12, 0xb94e, EN_VHF},
 	{227000, 1, 3, 15, 0x300, 0x4d12, 0xb94e, EN_VHF},
 	{380000, 1, 7, 15, 0x300, 0x4d12, 0xb94e, EN_VHF},
-#endif
-#ifdef CONFIG_BAND_UHF
 	{520000, 2, 0, 15, 0x300, 0x1d12, 0xb9ce, EN_UHF},
 	{550000, 2, 2, 15, 0x300, 0x1d12, 0xb9ce, EN_UHF},
 	{650000, 2, 3, 15, 0x300, 0x1d12, 0xb9ce, EN_UHF},
 	{750000, 2, 5, 15, 0x300, 0x1d12, 0xb9ce, EN_UHF},
 	{850000, 2, 6, 15, 0x300, 0x1d12, 0xb9ce, EN_UHF},
 	{900000, 2, 7, 15, 0x300, 0x1d12, 0xb9ce, EN_UHF},
-#endif
 };
 
 #define WBD     0x781		/* 1 1 1 1 0000 0 0 1 */
@@ -1140,10 +1104,8 @@ static int dib0090_tune(struct dvb_frontend *fe)
 	/* from these are needed :                               */
 	/* Cp,HFdiv,VCOband,SD,Num,Den,FB and REFDiv             */
 
-#ifdef CONFIG_SYS_ISDBT
 	if (state->fe->dtv_property_cache.delivery_system == SYS_ISDBT && state->fe->dtv_property_cache.isdbt_sb_mode == 1)
 		rf += 850;
-#endif
 
 	if (state->current_rf != rf) {
 		state->tuner_is_tuned = 0;
@@ -1241,9 +1203,7 @@ static int dib0090_tune(struct dvb_frontend *fe)
 				lo6 = (lo6 & 0xff9f) | 0x2;
 
 			dib0090_write_reg(state, 0x24, lo6 | EN_LO
-#ifdef CONFIG_DIB0090_USE_PWM_AGC
 					  | state->config->use_pwm_agc * EN_CRYSTAL
-#endif
 			    );
 
 			state->current_rf = rf;
@@ -1319,9 +1279,7 @@ static int dib0090_tune(struct dvb_frontend *fe)
 		c = 4;
 		i = 3;
 		dib0090_write_reg(state, 0x10, (c << 13) | (i << 11) | (WBD
-#ifdef CONFIG_DIB0090_USE_PWM_AGC
 									| (state->config->use_pwm_agc << 1)
-#endif
 				  ));
 		dib0090_write_reg(state, 0x09, (tune->lna_tune << 5) | (tune->lna_bias << 0));
 		dib0090_write_reg(state, 0x0c, tune->v2i);
-- 
1.7.0.4

[PATCH 3/4] drivers/media/video: Remove dead CONFIG_FB_OMAP2_FORCE_AUTO_UPDATE

[Christian Dietrich]

CONFIG_FB_OMAP2_FORCE_AUTO_UPDATE doesn't exist in Kconfig and is never defined anywhere
else, therefore removing all references for it from the source code.

Signed-off-by: Christian Dietrich <qy03fugy@stud.informatik.uni-erlangen.de>
---
 drivers/media/video/omap/omap_vout.c |    8 --------
 1 files changed, 0 insertions(+), 8 deletions(-)

diff --git a/drivers/media/video/omap/omap_vout.c b/drivers/media/video/omap/omap_vout.c
index 929073e..4ed51b1 100644
--- a/drivers/media/video/omap/omap_vout.c
+++ b/drivers/media/video/omap/omap_vout.c
@@ -2545,19 +2545,11 @@ static int __init omap_vout_probe(struct platform_device *pdev)
 			/* set the update mode */
 			if (def_display->caps &
 					OMAP_DSS_DISPLAY_CAP_MANUAL_UPDATE) {
-#ifdef CONFIG_FB_OMAP2_FORCE_AUTO_UPDATE
-				if (dssdrv->enable_te)
-					dssdrv->enable_te(def_display, 1);
-				if (dssdrv->set_update_mode)
-					dssdrv->set_update_mode(def_display,
-							OMAP_DSS_UPDATE_AUTO);
-#else	/* MANUAL_UPDATE */
 				if (dssdrv->enable_te)
 					dssdrv->enable_te(def_display, 0);
 				if (dssdrv->set_update_mode)
 					dssdrv->set_update_mode(def_display,
 							OMAP_DSS_UPDATE_MANUAL);
-#endif
 			} else {
 				if (dssdrv->set_update_mode)
 					dssdrv->set_update_mode(def_display,
-- 
1.7.0.4

[PATCH 4/4] drivers/media/video: Remove dead CONFIG_OLPC_X0_1

[Christian Dietrich]

CONFIG_OLPC_X0_1 doesn't exist in Kconfig and is never defined anywhere
else, therefore removing all references for it from the source code.

Signed-off-by: Christian Dietrich <qy03fugy@stud.informatik.uni-erlangen.de>
---
 drivers/media/video/ov7670.c |   37 -------------------------------------
 1 files changed, 0 insertions(+), 37 deletions(-)

diff --git a/drivers/media/video/ov7670.c b/drivers/media/video/ov7670.c
index 91c886a..309b272 100644
--- a/drivers/media/video/ov7670.c
+++ b/drivers/media/video/ov7670.c
@@ -409,42 +409,6 @@ static struct regval_list ov7670_fmt_raw[] = {
 
 /*
  * Low-level register I/O.
- *
- * Note that there are two versions of these.  On the XO 1, the
- * i2c controller only does SMBUS, so that's what we use.  The
- * ov7670 is not really an SMBUS device, though, so the communication
- * is not always entirely reliable.
- */
-#ifdef CONFIG_OLPC_XO_1
-static int ov7670_read(struct v4l2_subdev *sd, unsigned char reg,
-		unsigned char *value)
-{
-	struct i2c_client *client = v4l2_get_subdevdata(sd);
-	int ret;
-
-	ret = i2c_smbus_read_byte_data(client, reg);
-	if (ret >= 0) {
-		*value = (unsigned char)ret;
-		ret = 0;
-	}
-	return ret;
-}
-
-
-static int ov7670_write(struct v4l2_subdev *sd, unsigned char reg,
-		unsigned char value)
-{
-	struct i2c_client *client = v4l2_get_subdevdata(sd);
-	int ret = i2c_smbus_write_byte_data(client, reg, value);
-
-	if (reg == REG_COM7 && (value & COM7_RESET))
-		msleep(5);  /* Wait for reset to run */
-	return ret;
-}
-
-#else /* ! CONFIG_OLPC_XO_1 */
-/*
- * On most platforms, we'd rather do straight i2c I/O.
  */
 static int ov7670_read(struct v4l2_subdev *sd, unsigned char reg,
 		unsigned char *value)
@@ -498,7 +462,6 @@ static int ov7670_write(struct v4l2_subdev *sd, unsigned char reg,
 		msleep(5);  /* Wait for reset to run */
 	return ret;
 }
-#endif /* CONFIG_OLPC_XO_1 */
 
 
 /*
-- 
1.7.0.4

Re: [PATCH 4/4] drivers/media/video: Remove dead CONFIG_OLPC_X0_1

[Jonathan Corbet]

On Wed, 14 Jul 2010 15:21:48 +0200
Christian Dietrich <qy03fugy@stud.informatik.uni-erlangen.de> wrote:

> CONFIG_OLPC_X0_1 doesn't exist in Kconfig and is never defined anywhere
> else, therefore removing all references for it from the source code.

That symbol is, needless to say, an OLPC thing; it's in their
repository.  I do think they plan to upstream all of that at some
point, but I think they're a little busy at the moment.

Deleting this code will increase the delta between the OLPC and
mainline trees.  My preference would be for that not to happen.  If it
does, though, life will obviously go on, and this code can be restored
when the rest is upstreamed.  If you must do that, though, could I ask
that you preserve the CONFIG_OLPC_XO_1 version of the code, which is
the version which has traditionally been in the mainline?

jon

[PATCH 0/4] Removing dead code

[Christian Dietrich]

Hi all!
       
        As part of the VAMOS[0] research project at the University of
Erlangen we are looking at multiple integrity errors in linux'
configuration system.

        I've been running a check on the arch/frv sourcetree for
config Items not defined in Kconfig and found 4 such cases. Sourcecode
blocks depending on these Items are not reachable from a vanilla
kernel -- dead code. I've seen such dead blocks made on purpose
e.g. while integrating new features into the kernel but generally
they're just useless.

        Each of the patches in this patchset removes on such dead
config Item, I'd be glad if you consider applying them. I've been
doing deeper analysis of such issues before and can do so again but
I'm not so sure they were fastly usefull.


I wasn't able to build a vanilla kernel allyesconfig, therefore these
patches might break something. But because they are just removing dead
code it is unlikely.

Another problem i encountered was CONFIG_PREEMPT, which isn't
selectable in frv Kconfig because it doesn include
kernel/Kconfig.preempt. But there ist plenty of evidence for me, that
there is preemption support in frv.


        Please keep me informed of this patch getting confirmed /
merged so we can keep track of it.

Regards

        Christian Dietrich

[0] http://vamos1.informatik.uni-erlangen.de/

Christian Dietrich (4):
  arch/frv: Removing dead RAMKERNEL config option
  arch/frv: Removing dead HEARTBEAT config option
  arch/frv: Removing dead NO_KERNEL_MSG config option
  arch/frv: Removing dead DEBUG_STACK_USAGE config option

 arch/frv/include/asm/bug.h         |    4 ----
 arch/frv/include/asm/thread_info.h |   11 -----------
 arch/frv/kernel/debug-stub.c       |    2 --
 arch/frv/kernel/time.c             |    6 ------
 arch/frv/mm/init.c                 |   17 -----------------
 5 files changed, 0 insertions(+), 40 deletions(-)