summaryrefslogtreecommitdiff
path: root/drivers/staging/fbtft/fb_uc1611.c
diff options
context:
space:
mode:
Diffstat (limited to 'drivers/staging/fbtft/fb_uc1611.c')
-rw-r--r--drivers/staging/fbtft/fb_uc1611.c34
1 files changed, 20 insertions, 14 deletions
diff --git a/drivers/staging/fbtft/fb_uc1611.c b/drivers/staging/fbtft/fb_uc1611.c
index 65681d0fe200..f61e373c75e9 100644
--- a/drivers/staging/fbtft/fb_uc1611.c
+++ b/drivers/staging/fbtft/fb_uc1611.c
@@ -63,11 +63,17 @@ static int init_display(struct fbtft_par *par)
{
int ret;
- /* Set CS active high */
- par->spi->mode |= SPI_CS_HIGH;
+ /*
+ * Set CS active inverse polarity: just setting SPI_CS_HIGH does not
+ * work with GPIO based chip selects that are logically active high
+ * but inverted inside the GPIO library, so enforce inverted
+ * semantics.
+ */
+ par->spi->mode ^= SPI_CS_HIGH;
ret = spi_setup(par->spi);
if (ret) {
- dev_err(par->info->device, "Could not set SPI_CS_HIGH\n");
+ dev_err(par->info->device,
+ "Could not set inverse CS polarity\n");
return ret;
}
@@ -91,7 +97,7 @@ static int init_display(struct fbtft_par *par)
write_reg(par, 0x2C | (pump & 0x03));
/* Set inverse display */
- write_reg(par, 0xA6 | (0x01 & 0x01));
+ write_reg(par, 0xA6 | 0x01);
/* Set 4-bit grayscale mode */
write_reg(par, 0xD0 | (0x02 & 0x03));
@@ -157,8 +163,8 @@ static int set_var(struct fbtft_par *par)
/* Set RAM address control */
write_reg(par, 0x88
| (0x0 & 0x1) << 2 /* Increment positively */
- | (0x1 & 0x1) << 1 /* Increment page first */
- | (0x1 & 0x1)); /* Wrap around (default) */
+ | (0x1 << 1) /* Increment page first */
+ | 0x1); /* Wrap around (default) */
/* Set LCD mapping */
write_reg(par, 0xC0
@@ -171,11 +177,11 @@ static int set_var(struct fbtft_par *par)
write_reg(par, 0x88
| (0x0 & 0x1) << 2 /* Increment positively */
| (0x0 & 0x1) << 1 /* Increment column first */
- | (0x1 & 0x1)); /* Wrap around (default) */
+ | 0x1); /* Wrap around (default) */
/* Set LCD mapping */
write_reg(par, 0xC0
- | (0x1 & 0x1) << 2 /* Mirror Y ON */
+ | (0x1 << 2) /* Mirror Y ON */
| (0x0 & 0x1) << 1 /* Mirror X OFF */
| (0x0 & 0x1)); /* MS nibble last (default) */
break;
@@ -183,13 +189,13 @@ static int set_var(struct fbtft_par *par)
/* Set RAM address control */
write_reg(par, 0x88
| (0x0 & 0x1) << 2 /* Increment positively */
- | (0x1 & 0x1) << 1 /* Increment page first */
- | (0x1 & 0x1)); /* Wrap around (default) */
+ | (0x1 << 1) /* Increment page first */
+ | 0x1); /* Wrap around (default) */
/* Set LCD mapping */
write_reg(par, 0xC0
- | (0x1 & 0x1) << 2 /* Mirror Y ON */
- | (0x1 & 0x1) << 1 /* Mirror X ON */
+ | (0x1 << 2) /* Mirror Y ON */
+ | (0x1 << 1) /* Mirror X ON */
| (0x0 & 0x1)); /* MS nibble last (default) */
break;
default:
@@ -197,12 +203,12 @@ static int set_var(struct fbtft_par *par)
write_reg(par, 0x88
| (0x0 & 0x1) << 2 /* Increment positively */
| (0x0 & 0x1) << 1 /* Increment column first */
- | (0x1 & 0x1)); /* Wrap around (default) */
+ | 0x1); /* Wrap around (default) */
/* Set LCD mapping */
write_reg(par, 0xC0
| (0x0 & 0x1) << 2 /* Mirror Y OFF */
- | (0x1 & 0x1) << 1 /* Mirror X ON */
+ | (0x1 << 1) /* Mirror X ON */
| (0x0 & 0x1)); /* MS nibble last (default) */
break;
}