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authorAngelos Mouzakitis <a.mouzakitis@virtualopensystems.com>2023-10-10 14:33:42 +0000
committerAngelos Mouzakitis <a.mouzakitis@virtualopensystems.com>2023-10-10 14:33:42 +0000
commitaf1a266670d040d2f4083ff309d732d648afba2a (patch)
tree2fc46203448ddcc6f81546d379abfaeb323575e9 /roms/u-boot/drivers/i2c/s3c24x0_i2c.c
parente02cda008591317b1625707ff8e115a4841aa889 (diff)
Add submodule dependency filesHEADmaster
Change-Id: Iaf8d18082d3991dec7c0ebbea540f092188eb4ec
Diffstat (limited to 'roms/u-boot/drivers/i2c/s3c24x0_i2c.c')
-rw-r--r--roms/u-boot/drivers/i2c/s3c24x0_i2c.c349
1 files changed, 349 insertions, 0 deletions
diff --git a/roms/u-boot/drivers/i2c/s3c24x0_i2c.c b/roms/u-boot/drivers/i2c/s3c24x0_i2c.c
new file mode 100644
index 000000000..56f0f6988
--- /dev/null
+++ b/roms/u-boot/drivers/i2c/s3c24x0_i2c.c
@@ -0,0 +1,349 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * (C) Copyright 2002
+ * David Mueller, ELSOFT AG, d.mueller@elsoft.ch
+ */
+
+#include <common.h>
+#include <errno.h>
+#include <dm.h>
+#include <fdtdec.h>
+#if (defined CONFIG_EXYNOS4 || defined CONFIG_EXYNOS5)
+#include <log.h>
+#include <asm/arch/clk.h>
+#include <asm/arch/cpu.h>
+#include <asm/arch/pinmux.h>
+#else
+#include <asm/arch/s3c24x0_cpu.h>
+#endif
+#include <asm/global_data.h>
+#include <asm/io.h>
+#include <i2c.h>
+#include "s3c24x0_i2c.h"
+
+#ifndef CONFIG_SYS_I2C_S3C24X0_SLAVE
+#define SYS_I2C_S3C24X0_SLAVE_ADDR 0
+#else
+#define SYS_I2C_S3C24X0_SLAVE_ADDR CONFIG_SYS_I2C_S3C24X0_SLAVE
+#endif
+
+DECLARE_GLOBAL_DATA_PTR;
+
+/*
+ * Wait til the byte transfer is completed.
+ *
+ * @param i2c- pointer to the appropriate i2c register bank.
+ * @return I2C_OK, if transmission was ACKED
+ * I2C_NACK, if transmission was NACKED
+ * I2C_NOK_TIMEOUT, if transaction did not complete in I2C_TIMEOUT_MS
+ */
+
+static int WaitForXfer(struct s3c24x0_i2c *i2c)
+{
+ ulong start_time = get_timer(0);
+
+ do {
+ if (readl(&i2c->iiccon) & I2CCON_IRPND)
+ return (readl(&i2c->iicstat) & I2CSTAT_NACK) ?
+ I2C_NACK : I2C_OK;
+ } while (get_timer(start_time) < I2C_TIMEOUT_MS);
+
+ return I2C_NOK_TOUT;
+}
+
+static void read_write_byte(struct s3c24x0_i2c *i2c)
+{
+ clrbits_le32(&i2c->iiccon, I2CCON_IRPND);
+}
+
+static void i2c_ch_init(struct s3c24x0_i2c *i2c, int speed, int slaveadd)
+{
+ ulong freq, pres = 16, div;
+#if (defined CONFIG_EXYNOS4 || defined CONFIG_EXYNOS5)
+ freq = get_i2c_clk();
+#else
+ freq = get_PCLK();
+#endif
+ /* calculate prescaler and divisor values */
+ if ((freq / pres / (16 + 1)) > speed)
+ /* set prescaler to 512 */
+ pres = 512;
+
+ div = 0;
+ while ((freq / pres / (div + 1)) > speed)
+ div++;
+
+ /* set prescaler, divisor according to freq, also set ACKGEN, IRQ */
+ writel((div & 0x0F) | 0xA0 | ((pres == 512) ? 0x40 : 0), &i2c->iiccon);
+
+ /* init to SLAVE REVEIVE and set slaveaddr */
+ writel(0, &i2c->iicstat);
+ writel(slaveadd, &i2c->iicadd);
+ /* program Master Transmit (and implicit STOP) */
+ writel(I2C_MODE_MT | I2C_TXRX_ENA, &i2c->iicstat);
+}
+
+static int s3c24x0_i2c_set_bus_speed(struct udevice *dev, unsigned int speed)
+{
+ struct s3c24x0_i2c_bus *i2c_bus = dev_get_priv(dev);
+
+ i2c_bus->clock_frequency = speed;
+
+ i2c_ch_init(i2c_bus->regs, i2c_bus->clock_frequency,
+ SYS_I2C_S3C24X0_SLAVE_ADDR);
+
+ return 0;
+}
+
+/*
+ * cmd_type is 0 for write, 1 for read.
+ *
+ * addr_len can take any value from 0-255, it is only limited
+ * by the char, we could make it larger if needed. If it is
+ * 0 we skip the address write cycle.
+ */
+static int i2c_transfer(struct s3c24x0_i2c *i2c,
+ unsigned char cmd_type,
+ unsigned char chip,
+ unsigned char addr[],
+ unsigned char addr_len,
+ unsigned char data[],
+ unsigned short data_len)
+{
+ int i = 0, result;
+ ulong start_time = get_timer(0);
+
+ if (data == 0 || data_len == 0) {
+ /*Don't support data transfer of no length or to address 0 */
+ debug("i2c_transfer: bad call\n");
+ return I2C_NOK;
+ }
+
+ while (readl(&i2c->iicstat) & I2CSTAT_BSY) {
+ if (get_timer(start_time) > I2C_TIMEOUT_MS)
+ return I2C_NOK_TOUT;
+ }
+
+ writel(readl(&i2c->iiccon) | I2CCON_ACKGEN, &i2c->iiccon);
+
+ /* Get the slave chip address going */
+ writel(chip, &i2c->iicds);
+ if ((cmd_type == I2C_WRITE) || (addr && addr_len))
+ writel(I2C_MODE_MT | I2C_TXRX_ENA | I2C_START_STOP,
+ &i2c->iicstat);
+ else
+ writel(I2C_MODE_MR | I2C_TXRX_ENA | I2C_START_STOP,
+ &i2c->iicstat);
+
+ /* Wait for chip address to transmit. */
+ result = WaitForXfer(i2c);
+ if (result != I2C_OK)
+ goto bailout;
+
+ /* If register address needs to be transmitted - do it now. */
+ if (addr && addr_len) {
+ while ((i < addr_len) && (result == I2C_OK)) {
+ writel(addr[i++], &i2c->iicds);
+ read_write_byte(i2c);
+ result = WaitForXfer(i2c);
+ }
+ i = 0;
+ if (result != I2C_OK)
+ goto bailout;
+ }
+
+ switch (cmd_type) {
+ case I2C_WRITE:
+ while ((i < data_len) && (result == I2C_OK)) {
+ writel(data[i++], &i2c->iicds);
+ read_write_byte(i2c);
+ result = WaitForXfer(i2c);
+ }
+ break;
+
+ case I2C_READ:
+ if (addr && addr_len) {
+ /*
+ * Register address has been sent, now send slave chip
+ * address again to start the actual read transaction.
+ */
+ writel(chip, &i2c->iicds);
+
+ /* Generate a re-START. */
+ writel(I2C_MODE_MR | I2C_TXRX_ENA | I2C_START_STOP,
+ &i2c->iicstat);
+ read_write_byte(i2c);
+ result = WaitForXfer(i2c);
+
+ if (result != I2C_OK)
+ goto bailout;
+ }
+
+ while ((i < data_len) && (result == I2C_OK)) {
+ /* disable ACK for final READ */
+ if (i == data_len - 1)
+ writel(readl(&i2c->iiccon)
+ & ~I2CCON_ACKGEN,
+ &i2c->iiccon);
+ read_write_byte(i2c);
+ result = WaitForXfer(i2c);
+ data[i++] = readl(&i2c->iicds);
+ }
+ if (result == I2C_NACK)
+ result = I2C_OK; /* Normal terminated read. */
+ break;
+
+ default:
+ debug("i2c_transfer: bad call\n");
+ result = I2C_NOK;
+ break;
+ }
+
+bailout:
+ /* Send STOP. */
+ writel(I2C_MODE_MR | I2C_TXRX_ENA, &i2c->iicstat);
+ read_write_byte(i2c);
+
+ return result;
+}
+
+static int s3c24x0_i2c_probe(struct udevice *dev, uint chip, uint chip_flags)
+{
+ struct s3c24x0_i2c_bus *i2c_bus = dev_get_priv(dev);
+ uchar buf[1];
+ int ret;
+
+ buf[0] = 0;
+
+ /*
+ * What is needed is to send the chip address and verify that the
+ * address was <ACK>ed (i.e. there was a chip at that address which
+ * drove the data line low).
+ */
+ ret = i2c_transfer(i2c_bus->regs, I2C_READ, chip << 1, 0, 0, buf, 1);
+
+ return ret != I2C_OK;
+}
+
+static int s3c24x0_do_msg(struct s3c24x0_i2c_bus *i2c_bus, struct i2c_msg *msg,
+ int seq)
+{
+ struct s3c24x0_i2c *i2c = i2c_bus->regs;
+ bool is_read = msg->flags & I2C_M_RD;
+ uint status;
+ uint addr;
+ int ret, i;
+
+ if (!seq)
+ setbits_le32(&i2c->iiccon, I2CCON_ACKGEN);
+
+ /* Get the slave chip address going */
+ addr = msg->addr << 1;
+ writel(addr, &i2c->iicds);
+ status = I2C_TXRX_ENA | I2C_START_STOP;
+ if (is_read)
+ status |= I2C_MODE_MR;
+ else
+ status |= I2C_MODE_MT;
+ writel(status, &i2c->iicstat);
+ if (seq)
+ read_write_byte(i2c);
+
+ /* Wait for chip address to transmit */
+ ret = WaitForXfer(i2c);
+ if (ret)
+ goto err;
+
+ if (is_read) {
+ for (i = 0; !ret && i < msg->len; i++) {
+ /* disable ACK for final READ */
+ if (i == msg->len - 1)
+ clrbits_le32(&i2c->iiccon, I2CCON_ACKGEN);
+ read_write_byte(i2c);
+ ret = WaitForXfer(i2c);
+ msg->buf[i] = readl(&i2c->iicds);
+ }
+ if (ret == I2C_NACK)
+ ret = I2C_OK; /* Normal terminated read */
+ } else {
+ for (i = 0; !ret && i < msg->len; i++) {
+ writel(msg->buf[i], &i2c->iicds);
+ read_write_byte(i2c);
+ ret = WaitForXfer(i2c);
+ }
+ }
+
+err:
+ return ret;
+}
+
+static int s3c24x0_i2c_xfer(struct udevice *dev, struct i2c_msg *msg,
+ int nmsgs)
+{
+ struct s3c24x0_i2c_bus *i2c_bus = dev_get_priv(dev);
+ struct s3c24x0_i2c *i2c = i2c_bus->regs;
+ ulong start_time;
+ int ret, i;
+
+ start_time = get_timer(0);
+ while (readl(&i2c->iicstat) & I2CSTAT_BSY) {
+ if (get_timer(start_time) > I2C_TIMEOUT_MS) {
+ debug("Timeout\n");
+ return -ETIMEDOUT;
+ }
+ }
+
+ for (ret = 0, i = 0; !ret && i < nmsgs; i++)
+ ret = s3c24x0_do_msg(i2c_bus, &msg[i], i);
+
+ /* Send STOP */
+ writel(I2C_MODE_MR | I2C_TXRX_ENA, &i2c->iicstat);
+ read_write_byte(i2c);
+
+ return ret ? -EREMOTEIO : 0;
+}
+
+static int s3c_i2c_of_to_plat(struct udevice *dev)
+{
+ const void *blob = gd->fdt_blob;
+ struct s3c24x0_i2c_bus *i2c_bus = dev_get_priv(dev);
+ int node;
+
+ node = dev_of_offset(dev);
+
+ i2c_bus->regs = dev_read_addr_ptr(dev);
+
+ i2c_bus->id = pinmux_decode_periph_id(blob, node);
+
+ i2c_bus->clock_frequency =
+ dev_read_u32_default(dev, "clock-frequency",
+ I2C_SPEED_STANDARD_RATE);
+ i2c_bus->node = node;
+ i2c_bus->bus_num = dev_seq(dev);
+
+ exynos_pinmux_config(i2c_bus->id, 0);
+
+ i2c_bus->active = true;
+
+ return 0;
+}
+
+static const struct dm_i2c_ops s3c_i2c_ops = {
+ .xfer = s3c24x0_i2c_xfer,
+ .probe_chip = s3c24x0_i2c_probe,
+ .set_bus_speed = s3c24x0_i2c_set_bus_speed,
+};
+
+static const struct udevice_id s3c_i2c_ids[] = {
+ { .compatible = "samsung,s3c2440-i2c" },
+ { }
+};
+
+U_BOOT_DRIVER(i2c_s3c) = {
+ .name = "i2c_s3c",
+ .id = UCLASS_I2C,
+ .of_match = s3c_i2c_ids,
+ .of_to_plat = s3c_i2c_of_to_plat,
+ .priv_auto = sizeof(struct s3c24x0_i2c_bus),
+ .ops = &s3c_i2c_ops,
+};