spi: spi-ti-qspi: Fix FLEN and WLEN settings if bits_per_word is overridden
Each transfer can specify 8, 16 or 32 bits per word independently of
the default for the device being addressed. However, currently we
calculate the number of words in the frame assuming that the word size
is the device default.
If multiple transfers in the same message have differing
bits_per_word, we bitwise-or the different values in the WLEN register
field.
Fix both of these. Also rename 'frame_length' to 'frame_len_words' to
make clear that it's not a byte count like spi_message::frame_length.
Signed-off-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
Signed-off-by: Mark Brown <broonie@kernel.org>
Cc: stable@vger.kernel.org
diff --git a/drivers/spi/spi-ti-qspi.c b/drivers/spi/spi-ti-qspi.c
index eac3c96..0ee4139 100644
--- a/drivers/spi/spi-ti-qspi.c
+++ b/drivers/spi/spi-ti-qspi.c
@@ -94,6 +94,7 @@
#define QSPI_FLEN(n) ((n - 1) << 0)
#define QSPI_WLEN_MAX_BITS 128
#define QSPI_WLEN_MAX_BYTES 16
+#define QSPI_WLEN_MASK QSPI_WLEN(QSPI_WLEN_MAX_BITS)
/* STATUS REGISTER */
#define BUSY 0x01
@@ -450,7 +451,7 @@
struct spi_device *spi = m->spi;
struct spi_transfer *t;
int status = 0, ret;
- int frame_length;
+ unsigned int frame_len_words;
/* setup device control reg */
qspi->dc = 0;
@@ -462,14 +463,15 @@
if (spi->mode & SPI_CS_HIGH)
qspi->dc |= QSPI_CSPOL(spi->chip_select);
- frame_length = (m->frame_length << 3) / spi->bits_per_word;
-
- frame_length = clamp(frame_length, 0, QSPI_FRAME);
+ frame_len_words = 0;
+ list_for_each_entry(t, &m->transfers, transfer_list)
+ frame_len_words += t->len / (t->bits_per_word >> 3);
+ frame_len_words = min_t(unsigned int, frame_len_words, QSPI_FRAME);
/* setup command reg */
qspi->cmd = 0;
qspi->cmd |= QSPI_EN_CS(spi->chip_select);
- qspi->cmd |= QSPI_FLEN(frame_length);
+ qspi->cmd |= QSPI_FLEN(frame_len_words);
ti_qspi_write(qspi, qspi->dc, QSPI_SPI_DC_REG);
@@ -479,7 +481,8 @@
ti_qspi_disable_memory_map(spi);
list_for_each_entry(t, &m->transfers, transfer_list) {
- qspi->cmd |= QSPI_WLEN(t->bits_per_word);
+ qspi->cmd = ((qspi->cmd & ~QSPI_WLEN_MASK) |
+ QSPI_WLEN(t->bits_per_word));
ret = qspi_transfer_msg(qspi, t);
if (ret) {