Change in flashrom[master]: pickit2_spi.c: Refactor singleton states into reentrant pattern

[Nico Huber (Code Review)]

Nico Huber has submitted this change. ( https://review.coreboot.org/c/flashrom/+/52774 )

Change subject: pickit2_spi.c: Refactor singleton states into reentrant pattern
......................................................................

pickit2_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".

TEST=builds
BUG=b:185191942

Change-Id: Ibacc4738bee02c371c41583d321e0337128ad18a
Signed-off-by: Anastasia Klimchuk 
Reviewed-on: https://review.coreboot.org/c/flashrom/+/52774
Tested-by: build bot (Jenkins) 
Reviewed-by: Nico Huber 
Reviewed-by: Edward O'Callaghan 
Reviewed-by: Angel Pons 
---
M pickit2_spi.c
1 file changed, 37 insertions(+), 16 deletions(-)

Approvals:
  build bot (Jenkins): Verified
  Nico Huber: Looks good to me, but someone else must approve
  Angel Pons: Looks good to me, but someone else must approve
  Edward O'Callaghan: Looks good to me, approved

diff --git a/pickit2_spi.c b/pickit2_spi.c
index 367d0fc..3d0c775 100644
--- a/pickit2_spi.c
+++ b/pickit2_spi.c
@@ -52,7 +52,9 @@
    {0}
 };

-static libusb_device_handle *pickit2_handle;
+struct pickit2_spi_data {
+	libusb_device_handle *pickit2_handle;
+};

/* Default USB transaction timeout in ms */
 #define DFLT_TIMEOUT            10000
@@ -89,7 +91,7 @@
 #define SCR_VDD_OFF             0xFE
 #define SCR_VDD_ON              0xFF

-static int pickit2_get_firmware_version(void)
+static int pickit2_get_firmware_version(libusb_device_handle *pickit2_handle)
 {
    int ret;
    uint8_t command[CMD_LENGTH] = {CMD_GET_VERSION, CMD_END_OF_BUFFER};
@@ -113,7 +115,7 @@
    return 0;
 }

-static int pickit2_set_spi_voltage(int millivolt)
+static int pickit2_set_spi_voltage(libusb_device_handle *pickit2_handle, int millivolt)
 {
    double voltage_selector;
    switch (millivolt) {
@@ -172,7 +174,7 @@
    { NULL,		0x0 },
 };

-static int pickit2_set_spi_speed(unsigned int spispeed_idx)
+static int pickit2_set_spi_speed(libusb_device_handle *pickit2_handle, unsigned int spispeed_idx)
 {
    msg_pdbg("SPI speed is %sHz\n", spispeeds[spispeed_idx].name);

@@ -198,6 +200,7 @@
 static int pickit2_spi_send_command(const struct flashctx *flash, unsigned int writecnt, unsigned int readcnt,
    			     const unsigned char *writearr, unsigned char *readarr)
 {
+	struct pickit2_spi_data *pickit2_data = flash->mst->spi.data;

/* Maximum number of bytes per transaction (including command overhead) is 64. Lets play it safe
     * and always assume the worst case scenario of 20 bytes command overhead.
@@ -255,7 +258,8 @@
    buf[i++] = CMD_END_OF_BUFFER;

int transferred;
-	int ret = libusb_interrupt_transfer(pickit2_handle, ENDPOINT_OUT, buf, CMD_LENGTH, &transferred, DFLT_TIMEOUT);
+	int ret = libusb_interrupt_transfer(pickit2_data->pickit2_handle,
+					ENDPOINT_OUT, buf, CMD_LENGTH, &transferred, DFLT_TIMEOUT);

if (ret != 0) {
    	msg_perr("Send SPI failed!\n");
@@ -264,7 +268,8 @@

if (readcnt) {
    	int length = 0;
-		ret = libusb_interrupt_transfer(pickit2_handle, ENDPOINT_IN, buf, CMD_LENGTH, &length, DFLT_TIMEOUT);
+		ret = libusb_interrupt_transfer(pickit2_data->pickit2_handle,
+					ENDPOINT_IN, buf, CMD_LENGTH, &length, DFLT_TIMEOUT);

if (length == 0 || ret != 0) {
    		msg_perr("Receive SPI failed\n");
@@ -335,7 +340,7 @@
    return millivolt;
 }

-static const struct spi_master spi_master_pickit2 = {
+static struct spi_master spi_master_pickit2 = {
    .max_data_read	= 40,
    .max_data_write	= 40,
    .command	= pickit2_spi_send_command,
@@ -347,6 +352,8 @@

static int pickit2_shutdown(void *data)
 {
+	struct pickit2_spi_data *pickit2_data = data;
+
    /* Set all pins to float and turn voltages off */
    uint8_t command[CMD_LENGTH] = {
    	CMD_EXEC_SCRIPT,
@@ -363,18 +370,21 @@
    };

int transferred;
-	int ret = libusb_interrupt_transfer(pickit2_handle, ENDPOINT_OUT, command, CMD_LENGTH, &transferred, DFLT_TIMEOUT);
+	int ret = libusb_interrupt_transfer(pickit2_data->pickit2_handle,
+					ENDPOINT_OUT, command, CMD_LENGTH, &transferred, DFLT_TIMEOUT);

if (ret != 0) {
    	msg_perr("Command Shutdown failed!\n");
    	ret = 1;
    }
-	if (libusb_release_interface(pickit2_handle, 0) != 0) {
+	if (libusb_release_interface(pickit2_data->pickit2_handle, 0) != 0) {
    	msg_perr("Could not release USB interface!\n");
    	ret = 1;
    }
-	libusb_close(pickit2_handle);
+	libusb_close(pickit2_data->pickit2_handle);
    libusb_exit(NULL);
+
+	free(data);
    return ret;
 }

@@ -397,7 +407,8 @@
    	CMD_END_OF_BUFFER
    };

-
+	libusb_device_handle *pickit2_handle;
+	struct pickit2_spi_data *pickit2_data;
    int spispeed_idx = 0;
    char *spispeed = extract_programmer_param("spispeed");
    if (spispeed != NULL) {
@@ -458,16 +469,26 @@
    	return 1;
    }

-	if (pickit2_get_firmware_version())
+	pickit2_data = calloc(1, sizeof(*pickit2_data));
+	if (!pickit2_data) {
+		msg_perr("Unable to allocate space for SPI master data\n");
+		libusb_close(pickit2_handle);
+		libusb_exit(NULL);
+		return 1;
+	}
+	pickit2_data->pickit2_handle = pickit2_handle;
+	spi_master_pickit2.data = pickit2_data;
+
+	if (pickit2_get_firmware_version(pickit2_handle))
    	goto init_err_cleanup_exit;

/* Command Set SPI Speed */
-	if (pickit2_set_spi_speed(spispeed_idx))
+	if (pickit2_set_spi_speed(pickit2_handle, spispeed_idx))
    	goto init_err_cleanup_exit;

/* Command Set SPI Voltage */
    msg_pdbg("Setting voltage to %i mV.\n", millivolt);
-	if (pickit2_set_spi_voltage(millivolt) != 0)
+	if (pickit2_set_spi_voltage(pickit2_handle, millivolt) != 0)
    	goto init_err_cleanup_exit;

/* Perform basic setup.
@@ -478,13 +499,13 @@
    	goto init_err_cleanup_exit;
    }

-	if (register_shutdown(pickit2_shutdown, NULL))
+	if (register_shutdown(pickit2_shutdown, pickit2_data))
    	goto init_err_cleanup_exit;
    register_spi_master(&spi_master_pickit2);

return 0;

init_err_cleanup_exit:
-	pickit2_shutdown(NULL);
+	pickit2_shutdown(pickit2_data);
    return 1;
 }