Change in flashrom[master]: digilent_spi.c: Refactor singleton states into reentrant pattern

[Anastasia Klimchuk (Code Review)]

Anastasia Klimchuk has uploaded this change for review. ( https://review.coreboot.org/c/flashrom/+/54012 )

Change subject: digilent_spi.c: Refactor singleton states into reentrant pattern
......................................................................

digilent_spi.c: Refactor singleton states into reentrant pattern

Move global singleton states into a struct and store within
the spi_master data field for the life-time of the driver.

This is one of the steps on the way to move spi_master data
memory management behind the initialisation API, for more
context see other patches under the same topic "register_master_api".

BUG=b:185191942
TEST=builds

Change-Id: I91b842913d4402a4a1bec896f19c2fe1f34772b1
Signed-off-by: Anastasia Klimchuk 
---
M digilent_spi.c
1 file changed, 58 insertions(+), 47 deletions(-)

git pull ssh://review.coreboot.org:29418/flashrom refs/changes/12/54012/1

diff --git a/digilent_spi.c b/digilent_spi.c
index 0f7a9da..91a28b0 100644
--- a/digilent_spi.c
+++ b/digilent_spi.c
@@ -45,8 +45,10 @@
 #define	DATA_WRITE_EP		0x03
 #define	DATA_READ_EP		0x84

-static struct libusb_device_handle *handle = NULL;
-static bool reset_board;
+struct digilent_spi_data {
+	struct libusb_device_handle *handle;
+	bool reset_board;
+};

#define DIGILENT_VID		0x1443
 #define DIGILENT_JTAG_PID	0x0007
@@ -97,7 +99,7 @@
    CMD_SPI_TX_END		= 0x87,
 };

-static int do_command(uint8_t *req, int req_len, uint8_t *res, int res_len)
+static int do_command(uint8_t *req, int req_len, uint8_t *res, int res_len, struct libusb_device_handle *handle)
 {
    int tx_len = 0;
    int ret;
@@ -133,41 +135,41 @@
    return 0;
 }

-static int gpio_open(void)
+static int gpio_open(struct libusb_device_handle *handle)
 {
    uint8_t req[] = { 0x00, CMD_GPIO, CMD_GPIO_OPEN, 0x00 };
    uint8_t res[2];

-	return do_command(req, sizeof(req), res, sizeof(res));
+	return do_command(req, sizeof(req), res, sizeof(res), handle);
 }

-static int gpio_set_dir(uint8_t direction)
+static int gpio_set_dir(uint8_t direction, struct libusb_device_handle *handle)
 {
    uint8_t req[] = { 0x00, CMD_GPIO, CMD_GPIO_SET_DIR, 0x00,
    		  direction, 0x00, 0x00, 0x00 };
    uint8_t res[6];

-	return do_command(req, sizeof(req), res, sizeof(res));
+	return do_command(req, sizeof(req), res, sizeof(res), handle);
 }

-static int gpio_set_value(uint8_t value)
+static int gpio_set_value(uint8_t value, struct libusb_device_handle *handle)
 {
    uint8_t req[] = { 0x00, CMD_GPIO, CMD_GPIO_SET_VAL, 0x00,
    		  value, 0x00, 0x00, 0x00 };
    uint8_t res[2];

-	return do_command(req, sizeof(req), res, sizeof(res));
+	return do_command(req, sizeof(req), res, sizeof(res), handle);
 }

-static int spi_open(void)
+static int spi_open(struct libusb_device_handle *handle)
 {
    uint8_t req[] = { 0x00, CMD_SPI, CMD_SPI_OPEN, 0x00 };
    uint8_t res[2];

-	return do_command(req, sizeof(req), res, sizeof(res));
+	return do_command(req, sizeof(req), res, sizeof(res), handle);
 }

-static int spi_set_speed(uint32_t speed)
+static int spi_set_speed(uint32_t speed, struct libusb_device_handle *handle)
 {
    uint8_t req[] = { 0x00, CMD_SPI, CMD_SPI_SET_SPEED, 0x00,
    		  (speed) & 0xff,
@@ -178,7 +180,7 @@
    uint32_t real_speed;
    int ret;

-	ret = do_command(req, sizeof(req), res, sizeof(res));
+	ret = do_command(req, sizeof(req), res, sizeof(res), handle);
    if (ret)
    	return ret;

@@ -189,23 +191,23 @@
    return 0;
 }

-static int spi_set_mode(uint8_t mode)
+static int spi_set_mode(uint8_t mode, struct libusb_device_handle *handle)
 {
    uint8_t req[] = { 0x00, CMD_SPI, CMD_SPI_SET_MODE, 0x00, mode };
    uint8_t res[2];

-	return do_command(req, sizeof(req), res, sizeof(res));
+	return do_command(req, sizeof(req), res, sizeof(res), handle);
 }

-static int spi_set_cs(uint8_t cs)
+static int spi_set_cs(uint8_t cs, struct libusb_device_handle *handle)
 {
    uint8_t req[] = { 0x00, CMD_SPI, CMD_SPI_SET_CS, 0x00, cs };
    uint8_t res[2];

-	return do_command(req, sizeof(req), res, sizeof(res));
+	return do_command(req, sizeof(req), res, sizeof(res), handle);
 }

-static int spi_start_io(uint8_t read_follows, uint32_t write_len)
+static int spi_start_io(uint8_t read_follows, uint32_t write_len, struct libusb_device_handle *handle)
 {
    uint8_t req[] = { 0x00, CMD_SPI, CMD_SPI_START_IO, 0x00,
    		  0x00, 0x00, /* meaning unknown */
@@ -216,17 +218,17 @@
    		  (write_len >> 24) & 0xff };
    uint8_t res[2];

-	return do_command(req, sizeof(req), res, sizeof(res));
+	return do_command(req, sizeof(req), res, sizeof(res), handle);
 }

-static int spi_tx_end(uint8_t read_follows, uint32_t tx_len)
+static int spi_tx_end(uint8_t read_follows, uint32_t tx_len, struct libusb_device_handle *handle)
 {
    uint8_t req[] = { 0x00, CMD_SPI, CMD_SPI_TX_END, 0x00 };
    uint8_t res[read_follows ? 10 : 6];
    int ret;
    uint32_t count;

-	ret = do_command(req, sizeof(req), res, sizeof(res));
+	ret = do_command(req, sizeof(req), res, sizeof(res), handle);
    if (ret != 0)
    	return ret;

@@ -265,19 +267,20 @@
    int tx_len = 0;
    uint8_t buf[len];
    uint8_t read_follows = readcnt > 0 ? 1 : 0;
+	struct digilent_spi_data *digilent_data = flash->mst->spi.data;

memcpy(buf, writearr, writecnt);
    memset(buf + writecnt, 0xff, readcnt);

-	ret = spi_set_cs(0);
+	ret = spi_set_cs(0, digilent_data->handle);
    if (ret != 0)
    	return ret;

-	ret = spi_start_io(read_follows, writecnt);
+	ret = spi_start_io(read_follows, writecnt, digilent_data->handle);
    if (ret != 0)
    	return ret;

-	ret = libusb_bulk_transfer(handle, DATA_WRITE_EP, buf, len, &tx_len, USB_TIMEOUT);
+	ret = libusb_bulk_transfer(digilent_data->handle, DATA_WRITE_EP, buf, len, &tx_len, USB_TIMEOUT);
    if (ret != 0) {
    	msg_perr("%s: failed to write data: '%s'\n", __func__, libusb_error_name(ret));
    	return -1;
@@ -288,7 +291,7 @@
    }

if (read_follows) {
-		ret = libusb_bulk_transfer(handle, DATA_READ_EP, buf, len, &tx_len, USB_TIMEOUT);
+		ret = libusb_bulk_transfer(digilent_data->handle, DATA_READ_EP, buf, len, &tx_len, USB_TIMEOUT);
    	if (ret != 0) {
    		msg_perr("%s: failed to read data: '%s'\n", __func__, libusb_error_name(ret));
    		return -1;
@@ -299,11 +302,11 @@
    	}
    }

-	ret = spi_tx_end(read_follows, len);
+	ret = spi_tx_end(read_follows, len, digilent_data->handle);
    if (ret != 0)
    	return ret;

-	ret = spi_set_cs(1);
+	ret = spi_set_cs(1, digilent_data->handle);
    if (ret != 0)
    	return ret;

@@ -312,7 +315,7 @@
    return 0;
 }

-static const struct spi_master spi_master_digilent_spi = {
+static struct spi_master spi_master_digilent_spi = {
    .features	= SPI_MASTER_4BA,
    .max_data_read	= 252,
    .max_data_write	= 252,
@@ -326,16 +329,18 @@

static int digilent_spi_shutdown(void *data)
 {
-	if (reset_board)
-		gpio_set_dir(0);
+	struct digilent_spi_data *digilent_data = data;

-	libusb_close(handle);
-	handle = NULL;
+	if (digilent_data->reset_board)
+		gpio_set_dir(0, digilent_data->handle);

+	libusb_close(digilent_data->handle);
+
+	free(data);
    return 0;
 }

-static bool default_reset(void)
+static bool default_reset(struct libusb_device_handle *handle)
 {
    char board[17];

@@ -373,11 +378,8 @@
    char *p;
    uint32_t speed_hz = spispeeds[0].speed;
    int i;
-
-	if (handle != NULL) {
-		msg_cerr("%s: handle already set! Please report a bug at [e-mail]\n", __func__);
-		return -1;
-	}
+	struct libusb_device_handle *handle = NULL;
+	bool reset_board;

int32_t ret = libusb_init(NULL);
    if (ret < 0) {
@@ -425,32 +427,41 @@
    if (p && strlen(p))
    	reset_board = (p[0] == '1');
    else
-		reset_board = default_reset();
+		reset_board = default_reset(handle);
    free(p);

+
    if (reset_board) {
-		if (gpio_open() != 0)
+		if (gpio_open(handle) != 0)
    		goto close_handle;
-		if (gpio_set_dir(1) != 0)
+		if (gpio_set_dir(1, handle) != 0)
    		goto close_handle;
-		if (gpio_set_value(0) != 0)
+		if (gpio_set_value(0, handle) != 0)
    		goto close_handle;
    }

-	if (spi_open() != 0)
+	if (spi_open(handle) != 0)
    	goto close_handle;
-	if (spi_set_speed(speed_hz) != 0)
+	if (spi_set_speed(speed_hz, handle) != 0)
    	goto close_handle;
-	if (spi_set_mode(0x00) != 0)
+	if (spi_set_mode(0x00, handle) != 0)
    	goto close_handle;

-	register_shutdown(digilent_spi_shutdown, NULL);
+	struct digilent_spi_data *digilent_data = calloc(1, sizeof(*digilent_data));
+	if (!digilent_data) {
+		msg_perr("Unable to allocate space for SPI master data\n");
+		goto close_handle;
+	}
+	digilent_data->reset_board = reset_board;
+	digilent_data->handle = handle;
+	spi_master_digilent_spi.data = digilent_data;
+
+	register_shutdown(digilent_spi_shutdown, digilent_data);
    register_spi_master(&spi_master_digilent_spi);

return 0;

close_handle:
    libusb_close(handle);
-	handle = NULL;
    return -1;
 }