Commit e4342467 authored by Thierry Reding's avatar Thierry Reding Committed by Kamal Mostafa

drm/tegra: dpaux: Fix transfers larger than 4 bytes

commit 3c1dae0a upstream.

The DPAUX read/write FIFO registers aren't sequential in the register
space, causing transfers larger than 4 bytes to cause accesses to non-
existing FIFO registers.

Fixes: 6b6b6042 ("drm/tegra: Add eDP support")
Signed-off-by: default avatarThierry Reding <treding@nvidia.com>
Signed-off-by: default avatarKamal Mostafa <kamal@canonical.com>
parent 1d58609e
...@@ -72,34 +72,32 @@ static inline void tegra_dpaux_writel(struct tegra_dpaux *dpaux, ...@@ -72,34 +72,32 @@ static inline void tegra_dpaux_writel(struct tegra_dpaux *dpaux,
static void tegra_dpaux_write_fifo(struct tegra_dpaux *dpaux, const u8 *buffer, static void tegra_dpaux_write_fifo(struct tegra_dpaux *dpaux, const u8 *buffer,
size_t size) size_t size)
{ {
unsigned long offset = DPAUX_DP_AUXDATA_WRITE(0);
size_t i, j; size_t i, j;
for (i = 0; i < size; i += 4) { for (i = 0; i < DIV_ROUND_UP(size, 4); i++) {
size_t num = min_t(size_t, size - i, 4); size_t num = min_t(size_t, size - i * 4, 4);
unsigned long value = 0; unsigned long value = 0;
for (j = 0; j < num; j++) for (j = 0; j < num; j++)
value |= buffer[i + j] << (j * 8); value |= buffer[i * 4 + j] << (j * 8);
tegra_dpaux_writel(dpaux, value, offset++); tegra_dpaux_writel(dpaux, value, DPAUX_DP_AUXDATA_WRITE(i));
} }
} }
static void tegra_dpaux_read_fifo(struct tegra_dpaux *dpaux, u8 *buffer, static void tegra_dpaux_read_fifo(struct tegra_dpaux *dpaux, u8 *buffer,
size_t size) size_t size)
{ {
unsigned long offset = DPAUX_DP_AUXDATA_READ(0);
size_t i, j; size_t i, j;
for (i = 0; i < size; i += 4) { for (i = 0; i < DIV_ROUND_UP(size, 4); i++) {
size_t num = min_t(size_t, size - i, 4); size_t num = min_t(size_t, size - i * 4, 4);
unsigned long value; unsigned long value;
value = tegra_dpaux_readl(dpaux, offset++); value = tegra_dpaux_readl(dpaux, DPAUX_DP_AUXDATA_READ(i));
for (j = 0; j < num; j++) for (j = 0; j < num; j++)
buffer[i + j] = value >> (j * 8); buffer[i * 4 + j] = value >> (j * 8);
} }
} }
......
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