atsamd: Add support for programming SERCOM pins

Signed-off-by: Florian Heilmann <Florian.Heilmann@gmx.net>
Signed-off-by: Kevin O'Connor <kevin@koconnor.net>
This commit is contained in:
Kevin O'Connor 2019-02-19 00:32:37 -05:00
parent 8617cbcb76
commit c8d7e28a35
10 changed files with 500 additions and 41 deletions

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@ -721,6 +721,27 @@
# parameter must be provided.
# SAMD SERCOM configuration to specify which pins to use on a given SERCOM.
# One may define one section with the "samd_sercom" prefix per
# SERCOM available. Each SERCOM must be configured prior to using it as
# SPI or I2C peripheral. Place this config section above any other section
# that makes use of SPI or I2C buses.
#[samd_sercom 0]
#tx_pin:
# MOSI pin for SPI communication, or SDA (data) pin for I2C
# communication. The pin must have a valid pinmux configuration
# for the given SERCOM peripheral. This parameter must be provided.
#rx_pin:
# MISO pin for SPI communication. This pin is not used for I2C
# communication (I2C uses tx_pin for both sending and receiving).
# The pin must have a valid pinmux configuration for the given
# SERCOM peripheral. This parameter is optional.
#clk_pin:
# CLK pin for SPI communication, or SCL (clock) pin for I2C
# communication. The pin must have a valid pinmux configuration
# for the given SERCOM peripheral. This parameter must be provided.
# Statically configured AD5206 digipots connected via SPI bus (one may
# define any number of sections with an "ad5206" prefix).
#[ad5206 my_digipot]

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@ -6,6 +6,9 @@ All dates in this document are approximate.
# Changes
20190228: Users of SPI or I2C on SAMD21 boards must now specify the
bus pins via a [samd_sercom] config section.
20190224: The bed_shape option has been removed from bed_mesh. The
radius option has been renamed to bed_radius. Users with round beds
should supply the bed_radius and round_probe_count options.

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@ -0,0 +1,46 @@
# SAMD Sercom configuration
#
# Copyright (C) 2019 Florian Heilmann <Florian.Heilmann@gmx.net>
#
# This file may be distributed under the terms of the GNU GPLv3 license.
class SamdSERCOM:
def __init__(self, config):
self.printer = config.get_printer()
self.name = config.get_name().split()[1]
ppins = self.printer.lookup_object("pins")
try:
int(self.name)
except ValueError:
raise ppins.error("%s: SERCOM name must be an integer" % (
config.get_name(),))
self.tx_pin = config.get("tx_pin")
self.rx_pin = config.get("rx_pin", None)
self.clk_pin = config.get("clk_pin")
tx_pin_params = ppins.lookup_pin(self.tx_pin)
self.mcu = tx_pin_params['chip']
self.mcu.add_config_cmd(
"set_sercom_pin sercom_id=%s pin_type=%d pin=%s" % (
self.name, 0, self.tx_pin))
clk_pin_params = ppins.lookup_pin(self.clk_pin)
if self.mcu is not clk_pin_params['chip']:
raise ppins.error("%s: SERCOM pins must be on same mcu" % (
config.get_name(),))
self.mcu.add_config_cmd(
"set_sercom_pin sercom_id=%s pin_type=%d pin=%s" % (
self.name, 2, self.clk_pin))
if self.rx_pin:
rx_pin_params = ppins.lookup_pin(self.rx_pin)
if self.mcu is not rx_pin_params['chip']:
raise ppins.error("%s: SERCOM pins must be on same mcu" % (
config.get_name(),))
self.mcu.add_config_cmd(
"set_sercom_pin sercom_id=%s pin_type=%d pin=%s" % (
self.name, 1, self.rx_pin))
def load_config_prefix(config):
return SamdSERCOM(config)

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@ -8,7 +8,7 @@ config ATSAMD_SELECT
select HAVE_GPIO
select HAVE_GPIO_ADC
select HAVE_GPIO_I2C
select HAVE_GPIO_SPI if MACH_SAMD21
select HAVE_GPIO_SPI
select HAVE_GPIO_HARD_PWM if MACH_SAMD21
select HAVE_GPIO_BITBANGING
@ -85,5 +85,9 @@ config SERIAL
depends on !USBSERIAL
bool
default y
config HAVE_SERCOM
depends on HAVE_GPIO_I2C || HAVE_GPIO_SPI
bool
default y
endif

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@ -27,6 +27,7 @@ src-$(CONFIG_SERIAL) += atsamd/serial.c generic/serial_irq.c
src-$(CONFIG_HAVE_GPIO_ADC) += atsamd/adc.c
src-$(CONFIG_HAVE_GPIO_I2C) += atsamd/i2c.c
src-$(CONFIG_HAVE_GPIO_SPI) += atsamd/spi.c
src-$(CONFIG_HAVE_SERCOM) += atsamd/sercom.c
src-$(CONFIG_HAVE_GPIO_HARD_PWM) += atsamd/hard_pwm.c
src-$(CONFIG_MACH_SAMD21) += atsamd/watchdog.c
src-$(CONFIG_MACH_SAMD21) += atsamd/clock.c atsamd/timer.c generic/timer_irq.c

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@ -37,6 +37,7 @@ uint16_t gpio_adc_read(struct gpio_adc g);
void gpio_adc_cancel_sample(struct gpio_adc g);
struct spi_config {
void *ss;
uint32_t ctrla, baud;
};
struct spi_config spi_setup(uint32_t bus, uint8_t mode, uint32_t rate);
@ -45,6 +46,7 @@ void spi_transfer(struct spi_config config, uint8_t receive_data
, uint8_t len, uint8_t *data);
struct i2c_config {
void *si;
uint8_t addr;
};

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@ -1,5 +1,6 @@
// i2c support on samd
//
// Copyright (C) 2019 Florian Heilmann <Florian.Heilmann@gmx.net>
// Copyright (C) 2018-2019 Kevin O'Connor <kevin@koconnor.net>
//
// This file may be distributed under the terms of the GNU GPLv3 license.
@ -13,22 +14,14 @@
#define I2C_FREQ 100000
static void
i2c_init(void)
i2c_init(uint32_t bus, SercomI2cm *si)
{
static int have_run_init;
if (have_run_init)
static int have_run_init[8];
if (have_run_init[bus])
return;
have_run_init = 1;
// Setup clock
enable_pclock(SERCOM3_GCLK_ID_CORE, ID_SERCOM3);
// Configure SDA, SCL pins
gpio_peripheral(GPIO('A', 22), 'C', 0);
gpio_peripheral(GPIO('A', 23), 'C', 0);
have_run_init[bus] = 1;
// Configure i2c
SercomI2cm *si = &SERCOM3->I2CM;
si->CTRLA.reg = 0;
uint32_t areg = (SERCOM_I2CM_CTRLA_LOWTOUTEN
| SERCOM_I2CM_CTRLA_INACTOUT(3)
@ -36,7 +29,7 @@ i2c_init(void)
| SERCOM_I2CM_STATUS_MEXTTOUT
| SERCOM_I2CM_CTRLA_MODE(5));
si->CTRLA.reg = areg;
uint32_t freq = get_pclock_frequency(SERCOM3_GCLK_ID_CORE);
uint32_t freq = sercom_get_pclock_frequency(bus);
uint32_t baud = (freq/I2C_FREQ - 10 - freq*TIME_RISE/1000000000) / 2;
si->BAUD.reg = baud;
si->CTRLA.reg = areg | SERCOM_I2CM_CTRLA_ENABLE;
@ -52,10 +45,17 @@ i2c_init(void)
struct i2c_config
i2c_setup(uint32_t bus, uint32_t rate, uint8_t addr)
{
if (bus)
#ifdef SERCOM7
if (bus > 7)
#else
if (bus > 5)
#endif
shutdown("Unsupported i2c bus");
i2c_init();
return (struct i2c_config){ .addr=addr<<1 };
Sercom *sercom = sercom_enable_pclock(bus);
sercom_i2c_pins(bus);
SercomI2cm *si = &sercom->I2CM;
i2c_init(bus, si);
return (struct i2c_config){ .si=si, .addr=addr<<1 };
}
static void
@ -97,7 +97,7 @@ i2c_stop(SercomI2cm *si)
void
i2c_write(struct i2c_config config, uint8_t write_len, uint8_t *write)
{
SercomI2cm *si = &SERCOM3->I2CM;
SercomI2cm *si = (SercomI2cm *)config.si;
i2c_start(si, config.addr);
while (write_len--)
i2c_send_byte(si, *write++);

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@ -22,4 +22,9 @@ void enable_pclock(uint32_t pclk_id, uint32_t pm_id);
uint32_t get_pclock_frequency(uint32_t pclk_id);
void gpio_peripheral(uint32_t gpio, char ptype, int32_t pull_up);
Sercom * sercom_enable_pclock(uint32_t sercom_id);
uint32_t sercom_get_pclock_frequency(uint32_t sercom_id);
uint32_t sercom_spi_pins(uint32_t sercom_id);
void sercom_i2c_pins(uint32_t sercom_id);
#endif // internal.h

380
src/atsamd/sercom.c Normal file
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@ -0,0 +1,380 @@
// Handling of sercom pins
//
// Copyright (C) 2019 Florian Heilmann <Florian.Heilmann@gmx.net>
// Copyright (C) 2019 Kevin O'Connor <kevin@koconnor.net>
//
// This file may be distributed under the terms of the GNU GPLv3 license.
#include "internal.h" // sercom_enable
#include "command.h" // shutdown
#include "compiler.h" // ARRAY_SIZE
#include "sched.h" // sched_shutdown
/****************************************************************
* Available sercom blocks
****************************************************************/
struct sercom_bus {
Sercom *sercom;
uint32_t pclk_id, pm_id;
};
static const struct sercom_bus sercoms[] = {
{ SERCOM0, SERCOM0_GCLK_ID_CORE, ID_SERCOM0 },
{ SERCOM1, SERCOM1_GCLK_ID_CORE, ID_SERCOM1 },
{ SERCOM2, SERCOM2_GCLK_ID_CORE, ID_SERCOM2 },
{ SERCOM3, SERCOM3_GCLK_ID_CORE, ID_SERCOM3 },
{ SERCOM4, SERCOM4_GCLK_ID_CORE, ID_SERCOM4 },
{ SERCOM5, SERCOM5_GCLK_ID_CORE, ID_SERCOM5 },
#ifdef SERCOM6
{ SERCOM6, SERCOM6_GCLK_ID_CORE, ID_SERCOM6 },
{ SERCOM7, SERCOM7_GCLK_ID_CORE, ID_SERCOM7 },
#endif
};
Sercom *
sercom_enable_pclock(uint32_t sercom_id)
{
if (sercom_id >= ARRAY_SIZE(sercoms))
shutdown("Invalid sercom bus");
const struct sercom_bus *sb = &sercoms[sercom_id];
enable_pclock(sb->pclk_id, sb->pm_id);
return sb->sercom;
}
uint32_t
sercom_get_pclock_frequency(uint32_t sercom_id)
{
const struct sercom_bus *sb = &sercoms[sercom_id];
return get_pclock_frequency(sb->pclk_id);
}
/****************************************************************
* Pin configurations
****************************************************************/
struct sercom_pad {
uint8_t sercom_id, gpio, pad, ptype;
};
static const struct sercom_pad sercom_pads[] = {
#if CONFIG_MACH_SAMD21
{ 0, GPIO('A', 8), 0, 'C'},
{ 0, GPIO('A', 9), 1, 'C'},
{ 0, GPIO('A', 10), 2, 'C'},
{ 0, GPIO('A', 11), 3, 'C'},
{ 0, GPIO('A', 4), 0, 'D'},
{ 0, GPIO('A', 1), 1, 'D'},
{ 0, GPIO('A', 6), 2, 'D'},
{ 0, GPIO('A', 7), 3, 'D'},
{ 1, GPIO('A', 16), 0, 'C'},
{ 1, GPIO('A', 17), 1, 'C'},
{ 1, GPIO('A', 18), 2, 'C'},
{ 1, GPIO('A', 19), 3, 'C'},
{ 1, GPIO('A', 0), 0, 'D'},
{ 1, GPIO('A', 1), 1, 'D'},
{ 1, GPIO('A', 30), 2, 'D'},
{ 1, GPIO('A', 31), 3, 'D'},
{ 2, GPIO('A', 12), 0, 'C'},
{ 2, GPIO('A', 13), 1, 'C'},
{ 2, GPIO('A', 14), 2, 'C'},
{ 2, GPIO('A', 15), 3, 'C'},
{ 2, GPIO('A', 8), 0, 'D'},
{ 2, GPIO('A', 9), 1, 'D'},
{ 2, GPIO('A', 10), 2, 'D'},
{ 2, GPIO('A', 11), 3, 'D'},
{ 3, GPIO('A', 22), 0, 'C'},
{ 3, GPIO('A', 23), 1, 'C'},
{ 3, GPIO('A', 24), 2, 'C'},
{ 3, GPIO('A', 25), 3, 'C'},
{ 3, GPIO('A', 16), 0, 'D'},
{ 3, GPIO('A', 17), 1, 'D'},
{ 3, GPIO('A', 18), 2, 'D'},
{ 3, GPIO('A', 19), 3, 'D'},
{ 3, GPIO('A', 20), 2, 'D'},
{ 3, GPIO('A', 21), 3, 'D'},
{ 4, GPIO('B', 12), 0, 'C'},
{ 4, GPIO('B', 13), 1, 'C'},
{ 4, GPIO('B', 14), 2, 'C'},
{ 4, GPIO('B', 15), 3, 'C'},
{ 4, GPIO('B', 8), 0, 'D'},
{ 4, GPIO('B', 9), 1, 'D'},
{ 4, GPIO('B', 10), 2, 'D'},
{ 4, GPIO('B', 11), 3, 'D'},
{ 4, GPIO('A', 12), 0, 'D'},
{ 4, GPIO('A', 13), 1, 'D'},
{ 4, GPIO('A', 14), 2, 'D'},
{ 4, GPIO('A', 15), 3, 'D'},
{ 5, GPIO('B', 16), 0, 'C'},
{ 5, GPIO('B', 17), 1, 'C'},
{ 5, GPIO('A', 20), 2, 'C'},
{ 5, GPIO('A', 21), 3, 'C'},
{ 5, GPIO('A', 22), 0, 'D'},
{ 5, GPIO('A', 23), 1, 'D'},
{ 5, GPIO('A', 24), 2, 'D'},
{ 5, GPIO('A', 25), 3, 'D'},
{ 5, GPIO('B', 30), 0, 'D'},
{ 5, GPIO('B', 31), 1, 'D'},
{ 5, GPIO('B', 22), 2, 'D'},
{ 5, GPIO('B', 23), 3, 'D'},
{ 5, GPIO('B', 2), 0, 'D'},
{ 5, GPIO('B', 3), 1, 'D'},
{ 5, GPIO('B', 0), 2, 'D'},
{ 5, GPIO('B', 1), 3, 'D'},
#elif CONFIG_MACH_SAMD51
{ 0, GPIO('A', 8), 0, 'C'},
{ 0, GPIO('A', 9), 1, 'C'},
{ 0, GPIO('A', 10), 2, 'C'},
{ 0, GPIO('A', 11), 3, 'C'},
{ 0, GPIO('B', 24), 0, 'C'},
{ 0, GPIO('B', 25), 1, 'C'},
{ 0, GPIO('C', 24), 2, 'C'},
{ 0, GPIO('C', 25), 3, 'C'},
{ 0, GPIO('A', 4), 0, 'D'},
{ 0, GPIO('A', 5), 1, 'D'},
{ 0, GPIO('A', 6), 2, 'D'},
{ 0, GPIO('A', 7), 3, 'D'},
{ 0, GPIO('C', 17), 0, 'D'},
{ 0, GPIO('C', 16), 1, 'D'},
{ 0, GPIO('C', 18), 2, 'D'},
{ 0, GPIO('C', 19), 3, 'D'},
{ 1, GPIO('A', 16), 0, 'C'},
{ 1, GPIO('A', 17), 1, 'C'},
{ 1, GPIO('A', 18), 2, 'C'},
{ 1, GPIO('A', 19), 3, 'C'},
{ 1, GPIO('C', 22), 0, 'C'},
{ 1, GPIO('C', 23), 1, 'C'},
{ 1, GPIO('D', 20), 2, 'C'},
{ 1, GPIO('D', 21), 3, 'C'},
{ 1, GPIO('C', 27), 0, 'C'},
{ 1, GPIO('C', 28), 1, 'C'},
{ 1, GPIO('B', 22), 2, 'C'},
{ 1, GPIO('B', 23), 3, 'C'},
{ 1, GPIO('A', 0), 0, 'D'},
{ 1, GPIO('A', 1), 1, 'D'},
{ 1, GPIO('A', 30), 2, 'D'},
{ 1, GPIO('A', 31), 3, 'D'},
{ 2, GPIO('A', 12), 0, 'C'},
{ 2, GPIO('A', 13), 1, 'C'},
{ 2, GPIO('A', 14), 2, 'C'},
{ 2, GPIO('A', 15), 3, 'C'},
{ 2, GPIO('B', 26), 0, 'C'},
{ 2, GPIO('B', 27), 1, 'C'},
{ 2, GPIO('B', 28), 2, 'C'},
{ 2, GPIO('B', 29), 3, 'C'},
{ 2, GPIO('A', 9), 0, 'D'},
{ 2, GPIO('A', 8), 1, 'D'},
{ 2, GPIO('A', 10), 2, 'D'},
{ 2, GPIO('A', 11), 3, 'D'},
{ 2, GPIO('B', 25), 0, 'D'},
{ 2, GPIO('B', 24), 1, 'D'},
{ 2, GPIO('C', 24), 2, 'D'},
{ 2, GPIO('C', 25), 3, 'D'},
{ 3, GPIO('A', 22), 0, 'C'},
{ 3, GPIO('A', 23), 1, 'C'},
{ 3, GPIO('A', 24), 2, 'C'},
{ 3, GPIO('A', 25), 3, 'C'},
{ 3, GPIO('B', 20), 0, 'C'},
{ 3, GPIO('B', 21), 1, 'C'},
{ 3, GPIO('A', 20), 2, 'D'},
{ 3, GPIO('A', 21), 3, 'D'},
{ 3, GPIO('A', 17), 0, 'D'},
{ 3, GPIO('A', 16), 1, 'D'},
{ 3, GPIO('A', 18), 2, 'D'},
{ 3, GPIO('A', 19), 3, 'D'},
{ 3, GPIO('C', 23), 0, 'D'},
{ 3, GPIO('C', 22), 1, 'D'},
{ 3, GPIO('D', 20), 2, 'D'},
{ 3, GPIO('D', 21), 3, 'D'},
{ 4, GPIO('B', 12), 0, 'C'},
{ 4, GPIO('B', 13), 1, 'C'},
{ 4, GPIO('B', 14), 2, 'C'},
{ 4, GPIO('B', 15), 3, 'C'},
{ 4, GPIO('B', 8), 0, 'D'},
{ 4, GPIO('B', 9), 1, 'D'},
{ 4, GPIO('B', 10), 2, 'D'},
{ 4, GPIO('B', 11), 3, 'D'},
{ 4, GPIO('A', 13), 0, 'D'},
{ 4, GPIO('A', 12), 1, 'D'},
{ 4, GPIO('A', 14), 2, 'D'},
{ 4, GPIO('A', 15), 3, 'D'},
{ 4, GPIO('B', 27), 0, 'D'},
{ 4, GPIO('B', 26), 1, 'D'},
{ 4, GPIO('B', 28), 2, 'D'},
{ 4, GPIO('B', 29), 3, 'D'},
{ 5, GPIO('B', 16), 0, 'C'},
{ 5, GPIO('B', 17), 1, 'C'},
{ 5, GPIO('B', 18), 2, 'C'},
{ 5, GPIO('B', 19), 3, 'C'},
{ 5, GPIO('A', 23), 0, 'D'},
{ 5, GPIO('A', 22), 1, 'D'},
{ 5, GPIO('A', 20), 2, 'D'},
{ 5, GPIO('A', 21), 3, 'D'},
{ 5, GPIO('A', 24), 2, 'D'},
{ 5, GPIO('A', 25), 3, 'D'},
{ 5, GPIO('B', 22), 2, 'D'},
{ 5, GPIO('B', 23), 3, 'D'},
{ 5, GPIO('B', 31), 0, 'D'},
{ 5, GPIO('B', 30), 1, 'D'},
{ 5, GPIO('B', 0), 2, 'D'},
{ 5, GPIO('B', 1), 3, 'D'},
{ 5, GPIO('B', 2), 0, 'D'},
{ 5, GPIO('B', 3), 1, 'D'},
#ifdef SERCOM6
{ 6, GPIO('C', 16), 0, 'C'},
{ 6, GPIO('C', 17), 1, 'C'},
{ 6, GPIO('C', 18), 2, 'C'},
{ 6, GPIO('C', 19), 3, 'C'},
{ 6, GPIO('C', 4), 0, 'C'},
{ 6, GPIO('C', 5), 1, 'C'},
{ 6, GPIO('C', 6), 2, 'C'},
{ 6, GPIO('C', 7), 3, 'C'},
{ 6, GPIO('D', 9), 0, 'D'},
{ 6, GPIO('D', 8), 1, 'D'},
{ 6, GPIO('D', 10), 2, 'D'},
{ 6, GPIO('D', 11), 3, 'D'},
{ 6, GPIO('C', 13), 0, 'D'},
{ 6, GPIO('C', 12), 1, 'D'},
{ 6, GPIO('C', 14), 2, 'D'},
{ 6, GPIO('C', 15), 3, 'D'},
{ 6, GPIO('C', 10), 2, 'C'},
{ 6, GPIO('C', 11), 3, 'C'},
{ 7, GPIO('C', 12), 0, 'C'},
{ 7, GPIO('C', 13), 1, 'C'},
{ 7, GPIO('C', 14), 2, 'C'},
{ 7, GPIO('C', 15), 3, 'C'},
{ 7, GPIO('D', 8), 0, 'C'},
{ 7, GPIO('D', 9), 1, 'C'},
{ 7, GPIO('D', 10), 2, 'C'},
{ 7, GPIO('D', 11), 3, 'C'},
{ 7, GPIO('C', 10), 2, 'D'},
{ 7, GPIO('C', 11), 3, 'D'},
{ 7, GPIO('B', 21), 0, 'D'},
{ 7, GPIO('B', 20), 1, 'D'},
{ 7, GPIO('B', 18), 2, 'D'},
{ 7, GPIO('B', 19), 3, 'D'},
{ 7, GPIO('B', 30), 0, 'C'},
{ 7, GPIO('B', 31), 1, 'C'},
{ 7, GPIO('A', 30), 2, 'C'},
{ 7, GPIO('A', 31), 3, 'C'},
#endif
#endif
};
static const struct sercom_pad *
sercom_lookup_pad(uint32_t sercom_id, uint8_t pin)
{
const struct sercom_pad *sp = sercom_pads;
for (; ; sp++) {
if (sp >= &sercom_pads[ARRAY_SIZE(sercom_pads)])
shutdown("Invalid SERCOM configuration");
if (sp->sercom_id == sercom_id && sp->gpio == pin)
return sp;
}
}
/****************************************************************
* Runtime configuration
****************************************************************/
enum { TX_PIN, RX_PIN, CLK_PIN };
// Runtime configuration
struct sercom_pin {
uint8_t pins[3];
};
static struct sercom_pin sercom_pins[ARRAY_SIZE(sercoms)];
void
command_set_sercom_pin(uint32_t *args)
{
uint8_t sercom_id = args[0], pin_type = args[1], pin = args[2];
if (sercom_id >= ARRAY_SIZE(sercom_pins)
|| pin_type >= ARRAY_SIZE(sercom_pins[0].pins))
shutdown("Invalid SERCOM bus");
sercom_pins[sercom_id].pins[pin_type] = pin;
}
DECL_COMMAND(command_set_sercom_pin,
"set_sercom_pin sercom_id=%u pin_type=%u pin=%u");
/****************************************************************
* SPI dopo flag mapping
****************************************************************/
struct sercom_spi_map {
uint8_t tx_pad, clk_pad, dopo;
};
static const struct sercom_spi_map sercom_spi[] = {
{ 0, 1, 0 },
{ 3, 1, 2 },
#if CONFIG_MACH_SAMD21
{ 2, 3, 1 },
{ 0, 3, 3 },
#endif
};
static uint8_t
sercom_lookup_spi_dopo(uint8_t tx_pad, uint8_t clk_pad)
{
const struct sercom_spi_map *sm = sercom_spi;
for (; ; sm++) {
if (sm >= &sercom_spi[ARRAY_SIZE(sercom_spi)])
shutdown("Invalid combination of TX pin and CLK pin");
if (sm->tx_pad == tx_pad && sm->clk_pad == clk_pad)
return sm->dopo;
}
}
/****************************************************************
* Pin setup
****************************************************************/
uint32_t
sercom_spi_pins(uint32_t sercom_id)
{
uint8_t tx_pin = sercom_pins[sercom_id].pins[TX_PIN];
const struct sercom_pad *tx_sp = sercom_lookup_pad(sercom_id, tx_pin);
uint8_t rx_pin = sercom_pins[sercom_id].pins[RX_PIN];
const struct sercom_pad *rx_sp = sercom_lookup_pad(sercom_id, rx_pin);
uint8_t clk_pin = sercom_pins[sercom_id].pins[CLK_PIN];
const struct sercom_pad *clk_sp = sercom_lookup_pad(sercom_id, clk_pin);
uint8_t dopo = sercom_lookup_spi_dopo(tx_sp->pad, clk_sp->pad);
if (rx_sp->pad == tx_sp->pad || rx_sp->pad == clk_sp->pad)
shutdown("Sercom RX pad collides with TX or CLK pad");
gpio_peripheral(tx_pin, tx_sp->ptype, 0);
gpio_peripheral(rx_pin, rx_sp->ptype, 0);
gpio_peripheral(clk_pin, clk_sp->ptype, 0);
return SERCOM_SPI_CTRLA_DIPO(rx_sp->pad) | SERCOM_SPI_CTRLA_DOPO(dopo);
}
void
sercom_i2c_pins(uint32_t sercom_id)
{
uint8_t tx_pin = sercom_pins[sercom_id].pins[TX_PIN];
const struct sercom_pad *tx_sp = sercom_lookup_pad(sercom_id, tx_pin);
uint8_t clk_pin = sercom_pins[sercom_id].pins[CLK_PIN];
const struct sercom_pad *clk_sp = sercom_lookup_pad(sercom_id, clk_pin);
if (tx_sp->pad != 0 || clk_sp->pad != 1)
shutdown("TX pin not on PAD0 or CLK pin not on PAD1");
gpio_peripheral(tx_pin, tx_sp->ptype, 0);
gpio_peripheral(clk_pin, clk_sp->ptype, 0);
}

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@ -1,5 +1,6 @@
// spi support on samd
//
// Copyright (C) 2019 Florian Heilmann <Florian.Heilmann@gmx.net>
// Copyright (C) 2018-2019 Kevin O'Connor <kevin@koconnor.net>
//
// This file may be distributed under the terms of the GNU GPLv3 license.
@ -9,24 +10,14 @@
#include "gpio.h" // spi_setup
#include "sched.h" // sched_shutdown
static void
spi_init(uint32_t ctrla, uint32_t baud)
void
spi_init(uint32_t bus, SercomSpi *ss, uint32_t ctrla, uint32_t baud)
{
static int have_run_init;
if (have_run_init)
static int have_run_init[8];
if (have_run_init[bus])
return;
have_run_init = 1;
have_run_init[bus] = 1;
// Setup clock
enable_pclock(SERCOM4_GCLK_ID_CORE, ID_SERCOM4);
// Configure MISO, MOSI, SCK pins
gpio_peripheral(GPIO('A', 12), 'D', 0);
gpio_peripheral(GPIO('B', 10), 'D', 0);
gpio_peripheral(GPIO('B', 11), 'D', 0);
// Configure spi
SercomSpi *ss = &SERCOM4->SPI;
ss->CTRLA.reg = 0;
ss->CTRLA.reg = ctrla & ~SERCOM_SPI_CTRLA_ENABLE;
ss->CTRLB.reg = SERCOM_SPI_CTRLB_RXEN;
@ -37,24 +28,30 @@ spi_init(uint32_t ctrla, uint32_t baud)
struct spi_config
spi_setup(uint32_t bus, uint8_t mode, uint32_t rate)
{
if (bus)
#ifdef SERCOM7
if (bus > 7)
#else
if (bus > 5)
#endif
shutdown("Invalid spi bus");
uint32_t dipo_dopo = sercom_spi_pins(bus);
uint32_t ctrla = (SERCOM_SPI_CTRLA_MODE(3)
| (mode << SERCOM_SPI_CTRLA_CPHA_Pos)
| SERCOM_SPI_CTRLA_DIPO(0)
| SERCOM_SPI_CTRLA_DOPO(1)
| dipo_dopo
| SERCOM_SPI_CTRLA_ENABLE);
uint32_t baud = get_pclock_frequency(SERCOM4_GCLK_ID_CORE) / (2 * rate) - 1;
spi_init(ctrla, baud);
return (struct spi_config){ .ctrla = ctrla, .baud = baud };
Sercom *sercom = sercom_enable_pclock(bus);
SercomSpi *ss = &sercom->SPI;
uint32_t baud = sercom_get_pclock_frequency(bus) / (2 * rate) - 1;
spi_init(bus, ss, ctrla, baud);
return (struct spi_config){ .ss = ss, .ctrla = ctrla, .baud = baud };
}
void
spi_prepare(struct spi_config config)
{
uint32_t ctrla = config.ctrla, baud = config.baud;
SercomSpi *ss = &SERCOM4->SPI;
SercomSpi *ss = (SercomSpi *)config.ss;
if (ctrla == ss->CTRLA.reg && baud == ss->BAUD.reg)
return;
ss->CTRLA.reg = ctrla & ~SERCOM_SPI_CTRLA_ENABLE;
@ -67,7 +64,7 @@ void
spi_transfer(struct spi_config config, uint8_t receive_data
, uint8_t len, uint8_t *data)
{
SercomSpi *ss = &SERCOM4->SPI;
SercomSpi *ss = (SercomSpi *)config.ss;
if (receive_data) {
while (len--) {
ss->DATA.reg = *data;