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Diffstat (limited to 'chip/nrf51/i2c.c')
-rw-r--r--chip/nrf51/i2c.c304
1 files changed, 0 insertions, 304 deletions
diff --git a/chip/nrf51/i2c.c b/chip/nrf51/i2c.c
deleted file mode 100644
index ff23152c89..0000000000
--- a/chip/nrf51/i2c.c
+++ /dev/null
@@ -1,304 +0,0 @@
-/* Copyright 2014 The Chromium OS Authors. All rights reserved.
- * Use of this source code is governed by a BSD-style license that can be
- * found in the LICENSE file.
- */
-
-#include "clock.h"
-#include "common.h"
-#include "console.h"
-#include "gpio.h"
-#include "hooks.h"
-#include "i2c.h"
-#include "ppi.h"
-#include "registers.h"
-#include "task.h"
-#include "timer.h"
-#include "util.h"
-
-/* Console output macros */
-#define CPUTS(outstr) cputs(CC_I2C, outstr)
-#define CPRINTF(format, args...) cprintf(CC_I2C, format, ## args)
-#define CPRINTS(format, args...) cprints(CC_I2C, format, ## args)
-
-#define I2C_TIMEOUT 20000
-
-/* Keep track of the PPI channel used for each port */
-static int i2c_ppi_chan[] = {-1, -1};
-
-static void i2c_init_port(unsigned int port);
-
-/* board-specific setup for post-I2C module init */
-void __board_i2c_post_init(int port)
-{
-}
-
-void board_i2c_post_init(int port)
- __attribute__((weak, alias("__board_i2c_post_init")));
-
-static void i2c_init_port(unsigned int port)
-{
- NRF51_TWI_RXDRDY(port) = 0;
- NRF51_TWI_TXDSENT(port) = 0;
-
- NRF51_TWI_PSELSCL(port) = NRF51_TWI_SCL_PIN(port);
- NRF51_TWI_PSELSDA(port) = NRF51_TWI_SDA_PIN(port);
- NRF51_TWI_FREQUENCY(port) = NRF51_TWI_FREQ(port);
-
- NRF51_PPI_CHENCLR = 1 << i2c_ppi_chan[port];
-
- NRF51_PPI_EEP(i2c_ppi_chan[port]) = (uint32_t)&NRF51_TWI_BB(port);
- NRF51_PPI_TEP(i2c_ppi_chan[port]) =
- (uint32_t)&NRF51_TWI_SUSPEND(port);
-
- /* Master enable */
- NRF51_TWI_ENABLE(port) = NRF51_TWI_ENABLE_VAL;
-
- if (!(i2c_raw_get_scl(port) && (i2c_raw_get_sda(port))))
- CPRINTF("port %d could be wedged\n", port);
-}
-
-void i2c_init(void)
-{
- int i, rv;
-
- gpio_config_module(MODULE_I2C, 1);
-
- for (i = 0; i < i2c_ports_used; i++) {
- if (i2c_ppi_chan[i] == -1) {
- rv = ppi_request_channel(&i2c_ppi_chan[i]);
- ASSERT(rv == EC_SUCCESS);
-
- i2c_init_port(i);
- }
- }
-}
-
-static void dump_i2c_reg(int port)
-{
-#ifdef CONFIG_I2C_DEBUG
- CPRINTF("port : %01d\n", port);
- CPRINTF("Regs :\n");
- CPRINTF(" 1: INTEN : %08x\n", NRF51_TWI_INTEN(port));
- CPRINTF(" 2: ERRORSRC : %08x\n", NRF51_TWI_ERRORSRC(port));
- CPRINTF(" 3: ENABLE : %08x\n", NRF51_TWI_ENABLE(port));
- CPRINTF(" 4: PSELSCL : %08x\n", NRF51_TWI_PSELSCL(port));
- CPRINTF(" 5: PSELSDA : %08x\n", NRF51_TWI_PSELSDA(port));
- CPRINTF(" 6: RXD : %08x\n", NRF51_TWI_RXD(port));
- CPRINTF(" 7: TXD : %08x\n", NRF51_TWI_TXD(port));
- CPRINTF(" 8: FREQUENCY : %08x\n", NRF51_TWI_FREQUENCY(port));
- CPRINTF(" 9: ADDRESS : %08x\n", NRF51_TWI_ADDRESS(port));
- CPRINTF("Events :\n");
- CPRINTF(" STOPPED : %08x\n", NRF51_TWI_STOPPED(port));
- CPRINTF(" RXDRDY : %08x\n", NRF51_TWI_RXDRDY(port));
- CPRINTF(" TXDSENT : %08x\n", NRF51_TWI_TXDSENT(port));
- CPRINTF(" ERROR : %08x\n", NRF51_TWI_ERROR(port));
- CPRINTF(" BB : %08x\n", NRF51_TWI_BB(port));
-#endif /* CONFIG_I2C_DEBUG */
-}
-
-static void i2c_recover(int port)
-{
- /*
- * Recovery of the TWI peripheral:
- * To recover a TWI peripheral that has been locked up you must use
- * the following code.
- * After the recover function it is important to reconfigure all
- * relevant TWI registers explicitly to ensure that it operates
- * correctly.
- * TWI0:
- * NRF_TWI0->ENABLE =
- * TWI_ENABLE_ENABLE_Disabled << TWI_ENABLE_ENABLE_Pos;
- * *(uint32_t *)(NRF_TWI0_BASE + 0xFFC) = 0;
- * nrf_delay_us(5);
- * *(uint32_t *)(NRF_TWI0_BASE + 0xFFC) = 1;
- * NRF_TWI0->ENABLE =
- * TWI_ENABLE_ENABLE_Enabled << TWI_ENABLE_ENABLE_Pos;
- */
- NRF51_TWI_ENABLE(port) = NRF51_TWI_DISABLE_VAL;
- NRF51_TWI_POWER(port) = 0;
- udelay(5);
- NRF51_TWI_POWER(port) = 1;
-
- i2c_init_port(port);
-}
-
-static void handle_i2c_error(int port, int rv)
-{
- if (rv == EC_SUCCESS)
- return;
-
-#ifdef CONFIG_I2C_DEBUG
- if (rv != EC_ERROR_TIMEOUT)
- CPRINTF("handle_i2c_error %d\n", rv);
- else
- CPRINTF("handle_i2c_error: Timeout\n");
-
- dump_i2c_reg(port);
-#endif
-
- /* This may be a little too heavy handed. */
- i2c_recover(port);
-}
-
-static int i2c_master_write(const int port, const uint16_t slave_addr_flags,
- const uint8_t *data, int size, int stop)
-{
- int bytes_sent;
- int timeout = I2C_TIMEOUT;
-
- NRF51_TWI_ADDRESS(port) = I2C_STRIP_FLAGS(slave_addr_flags);
-
- /* Clear the sent bit */
- NRF51_TWI_TXDSENT(port) = 0;
-
- for (bytes_sent = 0; bytes_sent < size; bytes_sent++) {
- /*Send a byte */
- NRF51_TWI_TXD(port) = data[bytes_sent];
-
- /* Only send a start for the first byte */
- if (bytes_sent == 0)
- NRF51_TWI_STARTTX(port) = 1;
-
- /* Wait for ACK/NACK */
- timeout = I2C_TIMEOUT;
- while (timeout > 0 && NRF51_TWI_TXDSENT(port) == 0 &&
- NRF51_TWI_ERROR(port) == 0)
- timeout--;
-
- if (timeout == 0)
- return EC_ERROR_TIMEOUT;
-
- if (NRF51_TWI_ERROR(port))
- return EC_ERROR_UNKNOWN;
-
- /* Clear the sent bit */
- NRF51_TWI_TXDSENT(port) = 0;
- }
-
- if (stop) {
- NRF51_TWI_STOPPED(port) = 0;
- NRF51_TWI_STOP(port) = 1;
- timeout = 10;
- while (NRF51_TWI_STOPPED(port) == 0 && timeout > 0)
- timeout--;
- }
-
- return EC_SUCCESS;
-}
-
-static int i2c_master_read(const int port, const uint16_t slave_addr_flags,
- uint8_t *data, int size)
-{
- int curr_byte;
- int timeout = I2C_TIMEOUT;
-
- NRF51_TWI_ADDRESS(port) = I2C_STRIP_FLAGS(slave_addr_flags);
-
- if (size == 1) /* Last byte: stop after this one. */
- NRF51_PPI_TEP(i2c_ppi_chan[port]) =
- (uint32_t)&NRF51_TWI_STOP(port);
- else
- NRF51_PPI_TEP(i2c_ppi_chan[port]) =
- (uint32_t)&NRF51_TWI_SUSPEND(port);
- NRF51_PPI_CHENSET = 1 << i2c_ppi_chan[port];
-
- NRF51_TWI_RXDRDY(port) = 0;
- NRF51_TWI_STARTRX(port) = 1;
-
- for (curr_byte = 0; curr_byte < size; curr_byte++) {
-
- /* Wait for data */
- while (timeout > 0 && NRF51_TWI_RXDRDY(port) == 0 &&
- NRF51_TWI_ERROR(port) == 0)
- timeout--;
-
- if (timeout == 0)
- return EC_ERROR_TIMEOUT;
-
- if (NRF51_TWI_ERROR(port))
- return EC_ERROR_UNKNOWN;
-
- data[curr_byte] = NRF51_TWI_RXD(port);
- NRF51_TWI_RXDRDY(port) = 0;
-
- /* Second to the last byte: stop next time. */
- if (curr_byte == size-2)
- NRF51_PPI_TEP(i2c_ppi_chan[port]) =
- (uint32_t)&NRF51_TWI_STOP(port);
-
- /*
- * According to nRF51822-PAN v2.4 (Product Anomaly Notice),
- * the I2C locks up when RESUME is triggered too soon.
- * "the firmware should ensure that the time between receiving
- * the RXDRDY event and trigging the RESUME task is at least
- * two times the TWI clock period (i.e. 20 μs at 100 kbps).
- * Provided the TWI slave doesn’t do clock stretching during
- * the ACK bit, this will be enough to avoid the RESUME task
- * hit the end of the ACK bit. If this fails, a recovery of
- * the peripheral will be necessary, see i2c_recover.
- */
- udelay(20);
- NRF51_TWI_RESUME(port) = 1;
- }
-
- timeout = I2C_TIMEOUT;
- while (NRF51_TWI_STOPPED(port) == 0 && timeout > 0)
- timeout--;
-
- NRF51_TWI_STOP(port) = 0;
-
- NRF51_PPI_CHENCLR = 1 << i2c_ppi_chan[port];
-
- return EC_SUCCESS;
-}
-
-int chip_i2c_xfer(const int port, const uint16_t slave_addr_flags,
- const uint8_t *out, int out_bytes,
- uint8_t *in, int in_bytes, int flags)
-{
- int rv = EC_SUCCESS;
-
- ASSERT(out || !out_bytes);
- ASSERT(in || !in_bytes);
-
- if (out_bytes)
- rv = i2c_master_write(port, slave_addr_flags,
- out, out_bytes,
- in_bytes ? 0 : 1);
- if (rv == EC_SUCCESS && in_bytes)
- rv = i2c_master_read(port, slave_addr_flags,
- in, in_bytes);
-
- handle_i2c_error(port, rv);
-
- return rv;
-}
-
-int i2c_raw_get_scl(int port)
-{
- enum gpio_signal g;
-
- if (get_scl_from_i2c_port(port, &g) == EC_SUCCESS)
- return gpio_get_level(g);
-
- /* If no SCL pin defined for this port, then return 1 to appear idle. */
- return 1;
-}
-
-int i2c_raw_get_sda(int port)
-{
- enum gpio_signal g;
-
- if (get_sda_from_i2c_port(port, &g) == EC_SUCCESS)
- return gpio_get_level(g);
-
- /* If no SDA pin defined for this port, then return 1 to appear idle. */
- return 1;
-}
-
-int i2c_get_line_levels(int port)
-{
- return (i2c_raw_get_sda(port) ? I2C_LINE_SDA_HIGH : 0) |
- (i2c_raw_get_scl(port) ? I2C_LINE_SCL_HIGH : 0);
-}
-
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