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ramips: mt7621-spi: replace the driver with upstream staging one
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That driver is more efficient thanks to the refactor of spi reading operation.

Signed-off-by: Chuanhong Guo <gch981213@gmail.com>
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@981213 @blogic
981213 authored and blogic committed Nov 26, 2018
1 parent 20b09a2 commit a44f000
Showing 1 changed file with 121 additions and 98 deletions.
219 changes: 121 additions & 98 deletions target/linux/ramips/patches-4.14/0043-spi-add-mt7621-support.patch
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Original file line number Diff line number Diff line change
Expand Up @@ -5,6 +5,8 @@ Subject: [PATCH 43/53] spi: add mt7621 support

Signed-off-by: John Crispin <blogic@openwrt.org>
---
Note: This patch contains upstream mt7621-spi at 9c562d8411a54f6731cdc587c29968d9e8610c85

drivers/spi/Kconfig | 6 +
drivers/spi/Makefile | 1 +
drivers/spi/spi-mt7621.c | 480 ++++++++++++++++++++++++++++++++++++++++++++++
Expand Down Expand Up @@ -38,7 +40,7 @@ Signed-off-by: John Crispin <blogic@openwrt.org>
obj-$(CONFIG_SPI_OC_TINY) += spi-oc-tiny.o
--- /dev/null
+++ b/drivers/spi/spi-mt7621.c
@@ -0,0 +1,494 @@
@@ -0,0 +1,515 @@
+/*
+ * spi-mt7621.c -- MediaTek MT7621 SPI controller driver
+ *
Expand Down Expand Up @@ -96,7 +98,8 @@ Signed-off-by: John Crispin <blogic@openwrt.org>
+#define MT7621_CPOL BIT(4)
+#define MT7621_LSB_FIRST BIT(3)
+
+#define RT2880_SPI_MODE_BITS (SPI_CPOL | SPI_CPHA | SPI_LSB_FIRST | SPI_CS_HIGH)
+#define RT2880_SPI_MODE_BITS (SPI_CPOL | SPI_CPHA | \
+ SPI_LSB_FIRST | SPI_CS_HIGH)
+
+struct mt7621_spi;
+
Expand All @@ -106,6 +109,7 @@ Signed-off-by: John Crispin <blogic@openwrt.org>
+ unsigned int sys_freq;
+ unsigned int speed;
+ struct clk *clk;
+ int pending_write;
+
+ struct mt7621_spi_ops *ops;
+};
Expand All @@ -131,14 +135,13 @@ Signed-off-by: John Crispin <blogic@openwrt.org>
+
+ master |= 7 << 29;
+ master |= 1 << 2;
+#ifdef CONFIG_SOC_MT7620
+ if (duplex)
+ master |= 1 << 10;
+ else
+#endif
+ master &= ~(1 << 10);
+
+ mt7621_spi_write(rs, MT7621_SPI_MASTER, master);
+ rs->pending_write = 0;
+}
+
+static void mt7621_spi_set_cs(struct spi_device *spi, int enable)
Expand All @@ -147,7 +150,7 @@ Signed-off-by: John Crispin <blogic@openwrt.org>
+ int cs = spi->chip_select;
+ u32 polar = 0;
+
+ mt7621_spi_reset(rs, cs);
+ mt7621_spi_reset(rs, cs);
+ if (enable)
+ polar = BIT(cs);
+ mt7621_spi_write(rs, MT7621_SPI_POLAR, polar);
Expand Down Expand Up @@ -180,137 +183,166 @@ Signed-off-by: John Crispin <blogic@openwrt.org>
+ reg |= MT7621_LSB_FIRST;
+
+ reg &= ~(MT7621_CPHA | MT7621_CPOL);
+ switch(spi->mode & (SPI_CPOL | SPI_CPHA)) {
+ case SPI_MODE_0:
+ break;
+ case SPI_MODE_1:
+ reg |= MT7621_CPHA;
+ break;
+ case SPI_MODE_2:
+ reg |= MT7621_CPOL;
+ break;
+ case SPI_MODE_3:
+ reg |= MT7621_CPOL | MT7621_CPHA;
+ break;
+ switch (spi->mode & (SPI_CPOL | SPI_CPHA)) {
+ case SPI_MODE_0:
+ break;
+ case SPI_MODE_1:
+ reg |= MT7621_CPHA;
+ break;
+ case SPI_MODE_2:
+ reg |= MT7621_CPOL;
+ break;
+ case SPI_MODE_3:
+ reg |= MT7621_CPOL | MT7621_CPHA;
+ break;
+ }
+ mt7621_spi_write(rs, MT7621_SPI_MASTER, reg);
+
+ return 0;
+}
+
+static inline int mt7621_spi_wait_till_ready(struct spi_device *spi)
+static inline int mt7621_spi_wait_till_ready(struct mt7621_spi *rs)
+{
+ struct mt7621_spi *rs = spidev_to_mt7621_spi(spi);
+ int i;
+
+ for (i = 0; i < RALINK_SPI_WAIT_MAX_LOOP; i++) {
+ u32 status;
+
+ status = mt7621_spi_read(rs, MT7621_SPI_TRANS);
+ if ((status & SPITRANS_BUSY) == 0) {
+ if ((status & SPITRANS_BUSY) == 0)
+ return 0;
+ }
+ cpu_relax();
+ udelay(1);
+ }
+
+ return -ETIMEDOUT;
+}
+
+static int mt7621_spi_transfer_half_duplex(struct spi_master *master,
+ struct spi_message *m)
+static void mt7621_spi_read_half_duplex(struct mt7621_spi *rs,
+ int rx_len, u8 *buf)
+{
+ struct mt7621_spi *rs = spi_master_get_devdata(master);
+ struct spi_device *spi = m->spi;
+ unsigned int speed = spi->max_speed_hz;
+ struct spi_transfer *t = NULL;
+ int status = 0;
+ int i, len = 0;
+ int rx_len = 0;
+ u32 data[9] = { 0 };
+ u32 val;
+ /* Combine with any pending write, and perform one or
+ * more half-duplex transactions reading 'len' bytes.
+ * Data to be written is already in MT7621_SPI_DATA*
+ */
+ int tx_len = rs->pending_write;
+
+ mt7621_spi_wait_till_ready(spi);
+ rs->pending_write = 0;
+
+ list_for_each_entry(t, &m->transfers, transfer_list) {
+ const u8 *buf = t->tx_buf;
+ while (rx_len || tx_len) {
+ int i;
+ u32 val = (min(tx_len, 4) * 8) << 24;
+ int rx = min(rx_len, 32);
+
+ if (t->rx_buf)
+ rx_len += t->len;
+ if (tx_len > 4)
+ val |= (tx_len - 4) * 8;
+ val |= (rx * 8) << 12;
+ mt7621_spi_write(rs, MT7621_SPI_MOREBUF, val);
+
+ if (!buf)
+ continue;
+ tx_len = 0;
+
+ if (t->speed_hz < speed)
+ speed = t->speed_hz;
+ val = mt7621_spi_read(rs, MT7621_SPI_TRANS);
+ val |= SPI_CTL_START;
+ mt7621_spi_write(rs, MT7621_SPI_TRANS, val);
+
+ /*
+ * m25p80 might attempt to write more data than we can handle.
+ * truncate the message to what we can fit into the registers
+ */
+ if (len + t->len > 36)
+ t->len = 36 - len;
+ mt7621_spi_wait_till_ready(rs);
+
+ for (i = 0; i < t->len; i++, len++)
+ data[len / 4] |= buf[i] << (8 * (len & 3));
+ for (i = 0; i < rx; i++) {
+ if ((i % 4) == 0)
+ val = mt7621_spi_read(rs, MT7621_SPI_DATA0 + i);
+ *buf++ = val & 0xff;
+ val >>= 8;
+ }
+ rx_len -= i;
+ }
+}
+
+ if (WARN_ON(rx_len > 32)) {
+ status = -EIO;
+ goto msg_done;
+ }
+static inline void mt7621_spi_flush(struct mt7621_spi *rs)
+{
+ mt7621_spi_read_half_duplex(rs, 0, NULL);
+}
+
+ if (mt7621_spi_prepare(spi, speed)) {
+ status = -EIO;
+ goto msg_done;
+static void mt7621_spi_write_half_duplex(struct mt7621_spi *rs,
+ int tx_len, const u8 *buf)
+{
+ int val = 0;
+ int len = rs->pending_write;
+
+ if (len & 3) {
+ val = mt7621_spi_read(rs, MT7621_SPI_OPCODE + (len & ~3));
+ if (len < 4) {
+ val <<= (4 - len) * 8;
+ val = swab32(val);
+ }
+ }
+ data[0] = swab32(data[0]);
+ if (len < 4)
+ data[0] >>= (4 - len) * 8;
+
+ for (i = 0; i < len; i += 4)
+ mt7621_spi_write(rs, MT7621_SPI_OPCODE + i, data[i / 4]);
+
+ val = (min_t(int, len, 4) * 8) << 24;
+ if (len > 4)
+ val |= (len - 4) * 8;
+ val |= (rx_len * 8) << 12;
+ mt7621_spi_write(rs, MT7621_SPI_MOREBUF, val);
+
+ mt7621_spi_set_cs(spi, 1);
+ while (tx_len > 0) {
+ if (len >= 36) {
+ rs->pending_write = len;
+ mt7621_spi_flush(rs);
+ len = 0;
+ }
+
+ val = mt7621_spi_read(rs, MT7621_SPI_TRANS);
+ val |= SPI_CTL_START;
+ mt7621_spi_write(rs, MT7621_SPI_TRANS, val);
+ val |= *buf++ << (8 * (len & 3));
+ len++;
+ if ((len & 3) == 0) {
+ if (len == 4)
+ /* The byte-order of the opcode is weird! */
+ val = swab32(val);
+ mt7621_spi_write(rs, MT7621_SPI_OPCODE + len - 4, val);
+ val = 0;
+ }
+ tx_len -= 1;
+ }
+ if (len & 3) {
+ if (len < 4) {
+ val = swab32(val);
+ val >>= (4 - len) * 8;
+ }
+ mt7621_spi_write(rs, MT7621_SPI_OPCODE + (len & ~3), val);
+ }
+ rs->pending_write = len;
+}
+
+ mt7621_spi_wait_till_ready(spi);
+static int mt7621_spi_transfer_half_duplex(struct spi_master *master,
+ struct spi_message *m)
+{
+ struct mt7621_spi *rs = spi_master_get_devdata(master);
+ struct spi_device *spi = m->spi;
+ unsigned int speed = spi->max_speed_hz;
+ struct spi_transfer *t = NULL;
+ int status = 0;
+
+ mt7621_spi_set_cs(spi, 0);
+ mt7621_spi_wait_till_ready(rs);
+
+ for (i = 0; i < rx_len; i += 4)
+ data[i / 4] = mt7621_spi_read(rs, MT7621_SPI_DATA0 + i);
+ list_for_each_entry(t, &m->transfers, transfer_list)
+ if (t->speed_hz < speed)
+ speed = t->speed_hz;
+
+ m->actual_length = len + rx_len;
+ if (mt7621_spi_prepare(spi, speed)) {
+ status = -EIO;
+ goto msg_done;
+ }
+
+ len = 0;
+ mt7621_spi_set_cs(spi, 1);
+ m->actual_length = 0;
+ list_for_each_entry(t, &m->transfers, transfer_list) {
+ u8 *buf = t->rx_buf;
+
+ if (!buf)
+ continue;
+
+ for (i = 0; i < t->len; i++, len++)
+ buf[i] = data[len / 4] >> (8 * (len & 3));
+ if (t->rx_buf)
+ mt7621_spi_read_half_duplex(rs, t->len, t->rx_buf);
+ else if (t->tx_buf)
+ mt7621_spi_write_half_duplex(rs, t->len, t->tx_buf);
+ m->actual_length += t->len;
+ }
+ mt7621_spi_flush(rs);
+
+ mt7621_spi_set_cs(spi, 0);
+msg_done:
+ m->status = status;
+ spi_finalize_current_message(master);
+
+ return 0;
+}
+
+#ifdef CONFIG_SOC_MT7620
+static int mt7621_spi_transfer_full_duplex(struct spi_master *master,
+ struct spi_message *m)
+{
Expand All @@ -324,7 +356,7 @@ Signed-off-by: John Crispin <blogic@openwrt.org>
+ u32 data[9] = { 0 };
+ u32 val = 0;
+
+ mt7621_spi_wait_till_ready(spi);
+ mt7621_spi_wait_till_ready(rs);
+
+ list_for_each_entry(t, &m->transfers, transfer_list) {
+ const u8 *buf = t->tx_buf;
Expand Down Expand Up @@ -369,7 +401,7 @@ Signed-off-by: John Crispin <blogic@openwrt.org>
+ val |= SPI_CTL_START;
+ mt7621_spi_write(rs, MT7621_SPI_TRANS, val);
+
+ mt7621_spi_wait_till_ready(spi);
+ mt7621_spi_wait_till_ready(rs);
+
+ mt7621_spi_set_cs(spi, 0);
+
Expand All @@ -395,18 +427,15 @@ Signed-off-by: John Crispin <blogic@openwrt.org>
+
+ return 0;
+}
+#endif
+
+static int mt7621_spi_transfer_one_message(struct spi_master *master,
+ struct spi_message *m)
+{
+ struct spi_device *spi = m->spi;
+#ifdef CONFIG_SOC_MT7620
+ int cs = spi->chip_select;
+
+ if (cs)
+ return mt7621_spi_transfer_full_duplex(master, m);
+#endif
+ return mt7621_spi_transfer_half_duplex(master, m);
+}
+
Expand All @@ -433,11 +462,6 @@ Signed-off-by: John Crispin <blogic@openwrt.org>
+};
+MODULE_DEVICE_TABLE(of, mt7621_spi_match);
+
+static size_t mt7621_max_transfer_size(struct spi_device *spi)
+{
+ return 32;
+}
+
+static int mt7621_spi_probe(struct platform_device *pdev)
+{
+ const struct of_device_id *match;
Expand Down Expand Up @@ -483,7 +507,6 @@ Signed-off-by: John Crispin <blogic@openwrt.org>
+ master->bits_per_word_mask = SPI_BPW_MASK(8);
+ master->dev.of_node = pdev->dev.of_node;
+ master->num_chipselect = 2;
+ master->max_transfer_size = mt7621_max_transfer_size;
+
+ dev_set_drvdata(&pdev->dev, master);
+
Expand All @@ -493,6 +516,7 @@ Signed-off-by: John Crispin <blogic@openwrt.org>
+ rs->master = master;
+ rs->sys_freq = clk_get_rate(rs->clk);
+ rs->ops = ops;
+ rs->pending_write = 0;
+ dev_info(&pdev->dev, "sys_freq: %u\n", rs->sys_freq);
+
+ device_reset(&pdev->dev);
Expand Down Expand Up @@ -521,7 +545,6 @@ Signed-off-by: John Crispin <blogic@openwrt.org>
+static struct platform_driver mt7621_spi_driver = {
+ .driver = {
+ .name = DRIVER_NAME,
+ .owner = THIS_MODULE,
+ .of_match_table = mt7621_spi_match,
+ },
+ .probe = mt7621_spi_probe,
Expand Down

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