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path: root/drivers/net/can/spi/mcp251xfd/mcp251xfd-ring.c
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Diffstat (limited to 'drivers/net/can/spi/mcp251xfd/mcp251xfd-ring.c')
-rw-r--r--drivers/net/can/spi/mcp251xfd/mcp251xfd-ring.c417
1 files changed, 330 insertions, 87 deletions
diff --git a/drivers/net/can/spi/mcp251xfd/mcp251xfd-ring.c b/drivers/net/can/spi/mcp251xfd/mcp251xfd-ring.c
index 92f9e9b01289..bf3f0f150199 100644
--- a/drivers/net/can/spi/mcp251xfd/mcp251xfd-ring.c
+++ b/drivers/net/can/spi/mcp251xfd/mcp251xfd-ring.c
@@ -15,6 +15,7 @@
#include <asm/unaligned.h>
#include "mcp251xfd.h"
+#include "mcp251xfd-ram.h"
static inline u8
mcp251xfd_cmd_prepare_write_reg(const struct mcp251xfd_priv *priv,
@@ -53,6 +54,72 @@ mcp251xfd_cmd_prepare_write_reg(const struct mcp251xfd_priv *priv,
}
static void
+mcp251xfd_ring_init_tef(struct mcp251xfd_priv *priv, u16 *base)
+{
+ struct mcp251xfd_tef_ring *tef_ring;
+ struct spi_transfer *xfer;
+ u32 val;
+ u16 addr;
+ u8 len;
+ int i;
+
+ /* TEF */
+ tef_ring = priv->tef;
+ tef_ring->head = 0;
+ tef_ring->tail = 0;
+
+ /* TEF- and TX-FIFO have same number of objects */
+ *base = mcp251xfd_get_tef_obj_addr(priv->tx->obj_num);
+
+ /* FIFO IRQ enable */
+ addr = MCP251XFD_REG_TEFCON;
+ val = MCP251XFD_REG_TEFCON_TEFOVIE | MCP251XFD_REG_TEFCON_TEFNEIE;
+
+ len = mcp251xfd_cmd_prepare_write_reg(priv, &tef_ring->irq_enable_buf,
+ addr, val, val);
+ tef_ring->irq_enable_xfer.tx_buf = &tef_ring->irq_enable_buf;
+ tef_ring->irq_enable_xfer.len = len;
+ spi_message_init_with_transfers(&tef_ring->irq_enable_msg,
+ &tef_ring->irq_enable_xfer, 1);
+
+ /* FIFO increment TEF tail pointer */
+ addr = MCP251XFD_REG_TEFCON;
+ val = MCP251XFD_REG_TEFCON_UINC;
+ len = mcp251xfd_cmd_prepare_write_reg(priv, &tef_ring->uinc_buf,
+ addr, val, val);
+
+ for (i = 0; i < ARRAY_SIZE(tef_ring->uinc_xfer); i++) {
+ xfer = &tef_ring->uinc_xfer[i];
+ xfer->tx_buf = &tef_ring->uinc_buf;
+ xfer->len = len;
+ xfer->cs_change = 1;
+ xfer->cs_change_delay.value = 0;
+ xfer->cs_change_delay.unit = SPI_DELAY_UNIT_NSECS;
+ }
+
+ /* "cs_change == 1" on the last transfer results in an active
+ * chip select after the complete SPI message. This causes the
+ * controller to interpret the next register access as
+ * data. Set "cs_change" of the last transfer to "0" to
+ * properly deactivate the chip select at the end of the
+ * message.
+ */
+ xfer->cs_change = 0;
+
+ if (priv->tx_coalesce_usecs_irq || priv->tx_obj_num_coalesce_irq) {
+ val = MCP251XFD_REG_TEFCON_UINC |
+ MCP251XFD_REG_TEFCON_TEFOVIE |
+ MCP251XFD_REG_TEFCON_TEFHIE;
+
+ len = mcp251xfd_cmd_prepare_write_reg(priv,
+ &tef_ring->uinc_irq_disable_buf,
+ addr, val, val);
+ xfer->tx_buf = &tef_ring->uinc_irq_disable_buf;
+ xfer->len = len;
+ }
+}
+
+static void
mcp251xfd_tx_ring_init_tx_obj(const struct mcp251xfd_priv *priv,
const struct mcp251xfd_tx_ring *ring,
struct mcp251xfd_tx_obj *tx_obj,
@@ -88,84 +155,68 @@ mcp251xfd_tx_ring_init_tx_obj(const struct mcp251xfd_priv *priv,
ARRAY_SIZE(tx_obj->xfer));
}
-void mcp251xfd_ring_init(struct mcp251xfd_priv *priv)
+static void
+mcp251xfd_ring_init_tx(struct mcp251xfd_priv *priv, u16 *base, u8 *fifo_nr)
{
- struct mcp251xfd_tef_ring *tef_ring;
struct mcp251xfd_tx_ring *tx_ring;
- struct mcp251xfd_rx_ring *rx_ring, *prev_rx_ring = NULL;
struct mcp251xfd_tx_obj *tx_obj;
- struct spi_transfer *xfer;
u32 val;
u16 addr;
u8 len;
- int i, j;
-
- netdev_reset_queue(priv->ndev);
-
- /* TEF */
- tef_ring = priv->tef;
- tef_ring->head = 0;
- tef_ring->tail = 0;
-
- /* FIFO increment TEF tail pointer */
- addr = MCP251XFD_REG_TEFCON;
- val = MCP251XFD_REG_TEFCON_UINC;
- len = mcp251xfd_cmd_prepare_write_reg(priv, &tef_ring->uinc_buf,
- addr, val, val);
-
- for (j = 0; j < ARRAY_SIZE(tef_ring->uinc_xfer); j++) {
- xfer = &tef_ring->uinc_xfer[j];
- xfer->tx_buf = &tef_ring->uinc_buf;
- xfer->len = len;
- xfer->cs_change = 1;
- xfer->cs_change_delay.value = 0;
- xfer->cs_change_delay.unit = SPI_DELAY_UNIT_NSECS;
- }
-
- /* "cs_change == 1" on the last transfer results in an active
- * chip select after the complete SPI message. This causes the
- * controller to interpret the next register access as
- * data. Set "cs_change" of the last transfer to "0" to
- * properly deactivate the chip select at the end of the
- * message.
- */
- xfer->cs_change = 0;
+ int i;
- /* TX */
tx_ring = priv->tx;
tx_ring->head = 0;
tx_ring->tail = 0;
- tx_ring->base = mcp251xfd_get_tef_obj_addr(tx_ring->obj_num);
+ tx_ring->base = *base;
+ tx_ring->nr = 0;
+ tx_ring->fifo_nr = *fifo_nr;
+
+ *base = mcp251xfd_get_tx_obj_addr(tx_ring, tx_ring->obj_num);
+ *fifo_nr += 1;
/* FIFO request to send */
- addr = MCP251XFD_REG_FIFOCON(MCP251XFD_TX_FIFO);
+ addr = MCP251XFD_REG_FIFOCON(tx_ring->fifo_nr);
val = MCP251XFD_REG_FIFOCON_TXREQ | MCP251XFD_REG_FIFOCON_UINC;
len = mcp251xfd_cmd_prepare_write_reg(priv, &tx_ring->rts_buf,
addr, val, val);
mcp251xfd_for_each_tx_obj(tx_ring, tx_obj, i)
mcp251xfd_tx_ring_init_tx_obj(priv, tx_ring, tx_obj, len, i);
+}
+
+static void
+mcp251xfd_ring_init_rx(struct mcp251xfd_priv *priv, u16 *base, u8 *fifo_nr)
+{
+ struct mcp251xfd_rx_ring *rx_ring;
+ struct spi_transfer *xfer;
+ u32 val;
+ u16 addr;
+ u8 len;
+ int i, j;
- /* RX */
mcp251xfd_for_each_rx_ring(priv, rx_ring, i) {
rx_ring->head = 0;
rx_ring->tail = 0;
+ rx_ring->base = *base;
rx_ring->nr = i;
- rx_ring->fifo_nr = MCP251XFD_RX_FIFO(i);
+ rx_ring->fifo_nr = *fifo_nr;
- if (!prev_rx_ring)
- rx_ring->base =
- mcp251xfd_get_tx_obj_addr(tx_ring,
- tx_ring->obj_num);
- else
- rx_ring->base = prev_rx_ring->base +
- prev_rx_ring->obj_size *
- prev_rx_ring->obj_num;
+ *base = mcp251xfd_get_rx_obj_addr(rx_ring, rx_ring->obj_num);
+ *fifo_nr += 1;
- prev_rx_ring = rx_ring;
+ /* FIFO IRQ enable */
+ addr = MCP251XFD_REG_FIFOCON(rx_ring->fifo_nr);
+ val = MCP251XFD_REG_FIFOCON_RXOVIE |
+ MCP251XFD_REG_FIFOCON_TFNRFNIE;
+ len = mcp251xfd_cmd_prepare_write_reg(priv, &rx_ring->irq_enable_buf,
+ addr, val, val);
+ rx_ring->irq_enable_xfer.tx_buf = &rx_ring->irq_enable_buf;
+ rx_ring->irq_enable_xfer.len = len;
+ spi_message_init_with_transfers(&rx_ring->irq_enable_msg,
+ &rx_ring->irq_enable_xfer, 1);
/* FIFO increment RX tail pointer */
- addr = MCP251XFD_REG_FIFOCON(rx_ring->fifo_nr);
val = MCP251XFD_REG_FIFOCON_UINC;
len = mcp251xfd_cmd_prepare_write_reg(priv, &rx_ring->uinc_buf,
addr, val, val);
@@ -187,9 +238,149 @@ void mcp251xfd_ring_init(struct mcp251xfd_priv *priv)
* the chip select at the end of the message.
*/
xfer->cs_change = 0;
+
+ /* Use 1st RX-FIFO for IRQ coalescing. If enabled
+ * (rx_coalesce_usecs_irq or rx_max_coalesce_frames_irq
+ * is activated), use the last transfer to disable:
+ *
+ * - TFNRFNIE (Receive FIFO Not Empty Interrupt)
+ *
+ * and enable:
+ *
+ * - TFHRFHIE (Receive FIFO Half Full Interrupt)
+ * - or -
+ * - TFERFFIE (Receive FIFO Full Interrupt)
+ *
+ * depending on rx_max_coalesce_frames_irq.
+ *
+ * The RXOVIE (Overflow Interrupt) is always enabled.
+ */
+ if (rx_ring->nr == 0 && (priv->rx_coalesce_usecs_irq ||
+ priv->rx_obj_num_coalesce_irq)) {
+ val = MCP251XFD_REG_FIFOCON_UINC |
+ MCP251XFD_REG_FIFOCON_RXOVIE;
+
+ if (priv->rx_obj_num_coalesce_irq == rx_ring->obj_num)
+ val |= MCP251XFD_REG_FIFOCON_TFERFFIE;
+ else if (priv->rx_obj_num_coalesce_irq)
+ val |= MCP251XFD_REG_FIFOCON_TFHRFHIE;
+
+ len = mcp251xfd_cmd_prepare_write_reg(priv,
+ &rx_ring->uinc_irq_disable_buf,
+ addr, val, val);
+ xfer->tx_buf = &rx_ring->uinc_irq_disable_buf;
+ xfer->len = len;
+ }
}
}
+int mcp251xfd_ring_init(struct mcp251xfd_priv *priv)
+{
+ const struct mcp251xfd_rx_ring *rx_ring;
+ u16 base = 0, ram_used;
+ u8 fifo_nr = 1;
+ int i;
+
+ netdev_reset_queue(priv->ndev);
+
+ mcp251xfd_ring_init_tef(priv, &base);
+ mcp251xfd_ring_init_rx(priv, &base, &fifo_nr);
+ mcp251xfd_ring_init_tx(priv, &base, &fifo_nr);
+
+ /* mcp251xfd_handle_rxif() will iterate over all RX rings.
+ * Rings with their corresponding bit set in
+ * priv->regs_status.rxif are read out.
+ *
+ * If the chip is configured for only 1 RX-FIFO, and if there
+ * is an RX interrupt pending (RXIF in INT register is set),
+ * it must be the 1st RX-FIFO.
+ *
+ * We mark the RXIF of the 1st FIFO as pending here, so that
+ * we can skip the read of the RXIF register in
+ * mcp251xfd_read_regs_status() for the 1 RX-FIFO only case.
+ *
+ * If we use more than 1 RX-FIFO, this value gets overwritten
+ * in mcp251xfd_read_regs_status(), so set it unconditionally
+ * here.
+ */
+ priv->regs_status.rxif = BIT(priv->rx[0]->fifo_nr);
+
+ if (priv->tx_obj_num_coalesce_irq) {
+ netdev_dbg(priv->ndev,
+ "FIFO setup: TEF: 0x%03x: %2d*%zu bytes = %4zu bytes (coalesce)\n",
+ mcp251xfd_get_tef_obj_addr(0),
+ priv->tx_obj_num_coalesce_irq,
+ sizeof(struct mcp251xfd_hw_tef_obj),
+ priv->tx_obj_num_coalesce_irq *
+ sizeof(struct mcp251xfd_hw_tef_obj));
+
+ netdev_dbg(priv->ndev,
+ " 0x%03x: %2d*%zu bytes = %4zu bytes\n",
+ mcp251xfd_get_tef_obj_addr(priv->tx_obj_num_coalesce_irq),
+ priv->tx->obj_num - priv->tx_obj_num_coalesce_irq,
+ sizeof(struct mcp251xfd_hw_tef_obj),
+ (priv->tx->obj_num - priv->tx_obj_num_coalesce_irq) *
+ sizeof(struct mcp251xfd_hw_tef_obj));
+ } else {
+ netdev_dbg(priv->ndev,
+ "FIFO setup: TEF: 0x%03x: %2d*%zu bytes = %4zu bytes\n",
+ mcp251xfd_get_tef_obj_addr(0),
+ priv->tx->obj_num, sizeof(struct mcp251xfd_hw_tef_obj),
+ priv->tx->obj_num * sizeof(struct mcp251xfd_hw_tef_obj));
+ }
+
+ mcp251xfd_for_each_rx_ring(priv, rx_ring, i) {
+ if (rx_ring->nr == 0 && priv->rx_obj_num_coalesce_irq) {
+ netdev_dbg(priv->ndev,
+ "FIFO setup: RX-%u: FIFO %u/0x%03x: %2u*%u bytes = %4u bytes (coalesce)\n",
+ rx_ring->nr, rx_ring->fifo_nr,
+ mcp251xfd_get_rx_obj_addr(rx_ring, 0),
+ priv->rx_obj_num_coalesce_irq, rx_ring->obj_size,
+ priv->rx_obj_num_coalesce_irq * rx_ring->obj_size);
+
+ if (priv->rx_obj_num_coalesce_irq == MCP251XFD_FIFO_DEPTH)
+ continue;
+
+ netdev_dbg(priv->ndev,
+ " 0x%03x: %2u*%u bytes = %4u bytes\n",
+ mcp251xfd_get_rx_obj_addr(rx_ring,
+ priv->rx_obj_num_coalesce_irq),
+ rx_ring->obj_num - priv->rx_obj_num_coalesce_irq,
+ rx_ring->obj_size,
+ (rx_ring->obj_num - priv->rx_obj_num_coalesce_irq) *
+ rx_ring->obj_size);
+ } else {
+ netdev_dbg(priv->ndev,
+ "FIFO setup: RX-%u: FIFO %u/0x%03x: %2u*%u bytes = %4u bytes\n",
+ rx_ring->nr, rx_ring->fifo_nr,
+ mcp251xfd_get_rx_obj_addr(rx_ring, 0),
+ rx_ring->obj_num, rx_ring->obj_size,
+ rx_ring->obj_num * rx_ring->obj_size);
+ }
+ }
+
+ netdev_dbg(priv->ndev,
+ "FIFO setup: TX: FIFO %u/0x%03x: %2u*%u bytes = %4u bytes\n",
+ priv->tx->fifo_nr,
+ mcp251xfd_get_tx_obj_addr(priv->tx, 0),
+ priv->tx->obj_num, priv->tx->obj_size,
+ priv->tx->obj_num * priv->tx->obj_size);
+
+ netdev_dbg(priv->ndev,
+ "FIFO setup: free: %4d bytes\n",
+ MCP251XFD_RAM_SIZE - (base - MCP251XFD_RAM_START));
+
+ ram_used = base - MCP251XFD_RAM_START;
+ if (ram_used > MCP251XFD_RAM_SIZE) {
+ netdev_err(priv->ndev,
+ "Error during ring configuration, using more RAM (%u bytes) than available (%u bytes).\n",
+ ram_used, MCP251XFD_RAM_SIZE);
+ return -ENOMEM;
+ }
+
+ return 0;
+}
+
void mcp251xfd_ring_free(struct mcp251xfd_priv *priv)
{
int i;
@@ -200,40 +391,103 @@ void mcp251xfd_ring_free(struct mcp251xfd_priv *priv)
}
}
+static enum hrtimer_restart mcp251xfd_rx_irq_timer(struct hrtimer *t)
+{
+ struct mcp251xfd_priv *priv = container_of(t, struct mcp251xfd_priv,
+ rx_irq_timer);
+ struct mcp251xfd_rx_ring *ring = priv->rx[0];
+
+ if (test_bit(MCP251XFD_FLAGS_DOWN, priv->flags))
+ return HRTIMER_NORESTART;
+
+ spi_async(priv->spi, &ring->irq_enable_msg);
+
+ return HRTIMER_NORESTART;
+}
+
+static enum hrtimer_restart mcp251xfd_tx_irq_timer(struct hrtimer *t)
+{
+ struct mcp251xfd_priv *priv = container_of(t, struct mcp251xfd_priv,
+ tx_irq_timer);
+ struct mcp251xfd_tef_ring *ring = priv->tef;
+
+ if (test_bit(MCP251XFD_FLAGS_DOWN, priv->flags))
+ return HRTIMER_NORESTART;
+
+ spi_async(priv->spi, &ring->irq_enable_msg);
+
+ return HRTIMER_NORESTART;
+}
+
+const struct can_ram_config mcp251xfd_ram_config = {
+ .rx = {
+ .size[CAN_RAM_MODE_CAN] = sizeof(struct mcp251xfd_hw_rx_obj_can),
+ .size[CAN_RAM_MODE_CANFD] = sizeof(struct mcp251xfd_hw_rx_obj_canfd),
+ .min = MCP251XFD_RX_OBJ_NUM_MIN,
+ .max = MCP251XFD_RX_OBJ_NUM_MAX,
+ .def[CAN_RAM_MODE_CAN] = CAN_RAM_NUM_MAX,
+ .def[CAN_RAM_MODE_CANFD] = CAN_RAM_NUM_MAX,
+ .fifo_num = MCP251XFD_FIFO_RX_NUM,
+ .fifo_depth_min = MCP251XFD_RX_FIFO_DEPTH_MIN,
+ .fifo_depth_coalesce_min = MCP251XFD_RX_FIFO_DEPTH_COALESCE_MIN,
+ },
+ .tx = {
+ .size[CAN_RAM_MODE_CAN] = sizeof(struct mcp251xfd_hw_tef_obj) +
+ sizeof(struct mcp251xfd_hw_tx_obj_can),
+ .size[CAN_RAM_MODE_CANFD] = sizeof(struct mcp251xfd_hw_tef_obj) +
+ sizeof(struct mcp251xfd_hw_tx_obj_canfd),
+ .min = MCP251XFD_TX_OBJ_NUM_MIN,
+ .max = MCP251XFD_TX_OBJ_NUM_MAX,
+ .def[CAN_RAM_MODE_CAN] = MCP251XFD_TX_OBJ_NUM_CAN_DEFAULT,
+ .def[CAN_RAM_MODE_CANFD] = MCP251XFD_TX_OBJ_NUM_CANFD_DEFAULT,
+ .fifo_num = MCP251XFD_FIFO_TX_NUM,
+ .fifo_depth_min = MCP251XFD_TX_FIFO_DEPTH_MIN,
+ .fifo_depth_coalesce_min = MCP251XFD_TX_FIFO_DEPTH_COALESCE_MIN,
+ },
+ .size = MCP251XFD_RAM_SIZE,
+ .fifo_depth = MCP251XFD_FIFO_DEPTH,
+};
+
int mcp251xfd_ring_alloc(struct mcp251xfd_priv *priv)
{
- struct mcp251xfd_tx_ring *tx_ring;
+ const bool fd_mode = mcp251xfd_is_fd_mode(priv);
+ struct mcp251xfd_tx_ring *tx_ring = priv->tx;
struct mcp251xfd_rx_ring *rx_ring;
- int tef_obj_size, tx_obj_size, rx_obj_size;
- int tx_obj_num;
- int ram_free, i;
+ u8 tx_obj_size, rx_obj_size;
+ u8 rem, i;
- tef_obj_size = sizeof(struct mcp251xfd_hw_tef_obj);
- if (mcp251xfd_is_fd_mode(priv)) {
- tx_obj_num = MCP251XFD_TX_OBJ_NUM_CANFD;
+ /* switching from CAN-2.0 to CAN-FD mode or vice versa */
+ if (fd_mode != test_bit(MCP251XFD_FLAGS_FD_MODE, priv->flags)) {
+ struct can_ram_layout layout;
+
+ can_ram_get_layout(&layout, &mcp251xfd_ram_config, NULL, NULL, fd_mode);
+ priv->rx_obj_num = layout.default_rx;
+ tx_ring->obj_num = layout.default_tx;
+ }
+
+ if (fd_mode) {
tx_obj_size = sizeof(struct mcp251xfd_hw_tx_obj_canfd);
rx_obj_size = sizeof(struct mcp251xfd_hw_rx_obj_canfd);
+ set_bit(MCP251XFD_FLAGS_FD_MODE, priv->flags);
} else {
- tx_obj_num = MCP251XFD_TX_OBJ_NUM_CAN;
tx_obj_size = sizeof(struct mcp251xfd_hw_tx_obj_can);
rx_obj_size = sizeof(struct mcp251xfd_hw_rx_obj_can);
+ clear_bit(MCP251XFD_FLAGS_FD_MODE, priv->flags);
}
- tx_ring = priv->tx;
- tx_ring->obj_num = tx_obj_num;
tx_ring->obj_size = tx_obj_size;
- ram_free = MCP251XFD_RAM_SIZE - tx_obj_num *
- (tef_obj_size + tx_obj_size);
-
- for (i = 0;
- i < ARRAY_SIZE(priv->rx) && ram_free >= rx_obj_size;
- i++) {
- int rx_obj_num;
+ rem = priv->rx_obj_num;
+ for (i = 0; i < ARRAY_SIZE(priv->rx) && rem; i++) {
+ u8 rx_obj_num;
- rx_obj_num = ram_free / rx_obj_size;
- rx_obj_num = min(1 << (fls(rx_obj_num) - 1),
- MCP251XFD_RX_OBJ_NUM_MAX);
+ if (i == 0 && priv->rx_obj_num_coalesce_irq)
+ rx_obj_num = min_t(u8, priv->rx_obj_num_coalesce_irq * 2,
+ MCP251XFD_FIFO_DEPTH);
+ else
+ rx_obj_num = min_t(u8, rounddown_pow_of_two(rem),
+ MCP251XFD_FIFO_DEPTH);
+ rem -= rx_obj_num;
rx_ring = kzalloc(sizeof(*rx_ring) + rx_obj_size * rx_obj_num,
GFP_KERNEL);
@@ -241,29 +495,18 @@ int mcp251xfd_ring_alloc(struct mcp251xfd_priv *priv)
mcp251xfd_ring_free(priv);
return -ENOMEM;
}
+
rx_ring->obj_num = rx_obj_num;
rx_ring->obj_size = rx_obj_size;
priv->rx[i] = rx_ring;
-
- ram_free -= rx_ring->obj_num * rx_ring->obj_size;
}
priv->rx_ring_num = i;
- netdev_dbg(priv->ndev,
- "FIFO setup: TEF: %d*%d bytes = %d bytes, TX: %d*%d bytes = %d bytes\n",
- tx_obj_num, tef_obj_size, tef_obj_size * tx_obj_num,
- tx_obj_num, tx_obj_size, tx_obj_size * tx_obj_num);
+ hrtimer_init(&priv->rx_irq_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+ priv->rx_irq_timer.function = mcp251xfd_rx_irq_timer;
- mcp251xfd_for_each_rx_ring(priv, rx_ring, i) {
- netdev_dbg(priv->ndev,
- "FIFO setup: RX-%d: %d*%d bytes = %d bytes\n",
- i, rx_ring->obj_num, rx_ring->obj_size,
- rx_ring->obj_size * rx_ring->obj_num);
- }
-
- netdev_dbg(priv->ndev,
- "FIFO setup: free: %d bytes\n",
- ram_free);
+ hrtimer_init(&priv->tx_irq_timer, CLOCK_MONOTONIC, HRTIMER_MODE_REL);
+ priv->tx_irq_timer.function = mcp251xfd_tx_irq_timer;
return 0;
}