[PATCH 5.15 027/171] can: m_can: pci: fix iomap_read_fifo() and iomap_write_fifo()

Greg Kroah-Hartman
2021-12-13T10:21:08Z

From: Matthias Schiffer <matthias.schiffer@ew.tq-group.com>

commit d737de2d7cc3efdacbf17d4e22efc75697bd76d9 upstream.

The same fix that was previously done in m_can_platform in commit
99d173fbe894 ("can: m_can: fix iomap_read_fifo() and iomap_write_fifo()")
is required in m_can_pci as well to make iomap_read_fifo() and
iomap_write_fifo() work for val_count > 1.

Fixes: 812270e5445b ("can: m_can: Batch FIFO writes during CAN transmit")
Fixes: 1aa6772f64b4 ("can: m_can: Batch FIFO reads during CAN receive")
Link: https://lore.kernel.org/all/20211118144011.10921-1-matthias.schiffer@ew.tq-group.com
Cc: stable@vger.kernel.org
Cc: Matt Kline <matt@bitbashing.io>
Signed-off-by: Matthias Schiffer <matthias.schiffer@ew.tq-group.com>
Tested-by: Jarkko Nikula <jarkko.nikula@linux.intel.com>
Signed-off-by: Marc Kleine-Budde <mkl@pengutronix.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
drivers/net/can/m_can/m_can_pci.c | 14 ++++++++++++--
1 file changed, 12 insertions(+), 2 deletions(-)

--- a/drivers/net/can/m_can/m_can_pci.c
+++ b/drivers/net/can/m_can/m_can_pci.c
@@ -42,8 +42,13 @@ static u32 iomap_read_reg(struct m_can_c
static int iomap_read_fifo(struct m_can_classdev *cdev, int offset, void *val, size_t val_count)
{
struct m_can_pci_priv *priv = cdev_to_priv(cdev);
+ void __iomem *src = priv->base + offset;

- ioread32_rep(priv->base + offset, val, val_count);
+ while (val_count--) {
+ *(unsigned int *)val = ioread32(src);
+ val += 4;
+ src += 4;
+ }

return 0;
}
@@ -61,8 +66,13 @@ static int iomap_write_fifo(struct m_can
const void *val, size_t val_count)
{
struct m_can_pci_priv *priv = cdev_to_priv(cdev);
+ void __iomem *dst = priv->base + offset;

- iowrite32_rep(priv->base + offset, val, val_count);
+ while (val_count--) {
+ iowrite32(*(unsigned int *)val, dst);
+ val += 4;
+ dst += 4;
+ }

return 0;
}