[flashrom-gerrit] Change in flashrom[master]: raiden_debug_spi.c: Clean up global state

[Edward O'Callaghan (Code Review)]

Edward O'Callaghan has uploaded this change for review. ( https://review.coreboot.org/c/flashrom/+/40105 )

Change subject: raiden_debug_spi.c: Clean up global state
......................................................................

raiden_debug_spi.c: Clean up global state

The Chromium flashrom fork has very poor dispatch logic whereas
upstream has proper inversion of control with a generic 'data'
void * member for stuff long-lived state in. Leverage the member
to store the USB descriptor state in during the life-time of the
spi master.

BUG=b:140394053
BRANCH=none
TEST=builds

Change-Id: Ida9dce97fef2c6dfd68a278c879917fdd3ff7fef
Signed-off-by: Edward O'Callaghan 
---
M raiden_debug_spi.c
1 file changed, 48 insertions(+), 15 deletions(-)

git pull ssh://review.coreboot.org:29418/flashrom refs/changes/05/40105/1

diff --git a/raiden_debug_spi.c b/raiden_debug_spi.c
index 173e355..913ee45 100644
--- a/raiden_debug_spi.c
+++ b/raiden_debug_spi.c
@@ -161,9 +161,11 @@
  */
 #define TRANSFER_TIMEOUT_MS     (200 + 800)

-struct usb_device *device       = NULL;
-uint8_t            in_endpoint  = 0;
-uint8_t            out_endpoint = 0;
+struct raiden_debug_spi_data {
+	struct usb_device *dev;
+	uint8_t in_ep;
+	uint8_t out_ep;
+};

typedef struct {
    int8_t write_count;
@@ -200,6 +202,12 @@
    return true;
 }

+static const struct raiden_debug_spi_data *
+	get_raiden_data_from_context(const struct flashctx *flash)
+{
+	return (const struct raiden_debug_spi_data *)flash->mst->spi.data;
+}
+
 static int write_command(const struct flashctx *flash,
    	unsigned int write_count,
    	unsigned int read_count,
@@ -210,6 +218,7 @@
    int transferred;
    int ret;
    usb_spi_command_t command_packet;
+	const struct raiden_debug_spi_data * ctx_data = get_raiden_data_from_context(flash);

if (write_count > PAYLOAD_SIZE) {
    	msg_perr("Raiden: Invalid write_count of %d\n", write_count);
@@ -226,8 +235,8 @@

memcpy(command_packet.data, write_buffer, write_count);

-	ret = LIBUSB(libusb_bulk_transfer(device->handle,
-				out_endpoint,
+	ret = LIBUSB(libusb_bulk_transfer(ctx_data->dev->handle,
+				ctx_data->out_ep,
    			(void*)&command_packet,
    			write_count + PACKET_HEADER_SIZE,
    			&transferred,
@@ -258,9 +267,10 @@
    int transferred;
    int ret;
    usb_spi_response_t response_packet;
+	const struct raiden_debug_spi_data * ctx_data = get_raiden_data_from_context(flash);

-	ret = LIBUSB(libusb_bulk_transfer(device->handle,
-				in_endpoint,
+	ret = LIBUSB(libusb_bulk_transfer(ctx_data->dev->handle,
+				ctx_data->in_ep,
    			(void*)&response_packet,
    			read_count + PACKET_HEADER_SIZE,
    			&transferred,
@@ -403,16 +413,19 @@
    return 0;
 }

-static int shutdown(void * data)
+static int raiden_debug_spi_shutdown(void * data)
 {
+	struct raiden_debug_spi_data * ctx_data =
+		(struct raiden_debug_spi_data *)data;
+
    int ret = LIBUSB(libusb_control_transfer(
-				device->handle,
+				ctx_data->dev->handle,
    			LIBUSB_ENDPOINT_OUT |
    			LIBUSB_REQUEST_TYPE_VENDOR |
    			LIBUSB_RECIPIENT_INTERFACE,
    			RAIDEN_DEBUG_SPI_REQ_DISABLE,
    			0,
-				device->interface_descriptor->bInterfaceNumber,
+				ctx_data->dev->interface_descriptor->bInterfaceNumber,
    			NULL,
    			0,
    			TRANSFER_TIMEOUT_MS));
@@ -421,10 +434,9 @@
    	return ret;
    }

-	usb_device_free(device);
-
-	device = NULL;
+	usb_device_free(ctx_data->dev);
    libusb_exit(NULL);
+	free(ctx_data);

return 0;
 }
@@ -458,11 +470,20 @@
    	dev = usb_device_free(dev);
 }

+static int register_raiden_debug_spi_master(void *ptr)
+{
+	struct spi_master mst = spi_master_raiden_debug;
+	mst.data = ptr;
+
+	return register_spi_master(&mst);
+}
+
 int raiden_debug_spi_init(void)
 {
    struct usb_match match;
    char *serial = extract_programmer_param("serial");
    struct usb_device *current;
+	struct usb_device *device = NULL;
    int found = 0;
    int ret;

@@ -489,6 +510,8 @@
    	return ret;
    }

+	uint8_t in_endpoint  = 0;
+	uint8_t out_endpoint = 0;
    while (current) {
    	device = current;

@@ -576,8 +599,18 @@
    	(request_enable == RAIDEN_DEBUG_SPI_REQ_ENABLE_EC))
    	usleep(50 * 1000);

-	register_spi_master(&spi_master_raiden_debug);
-	register_shutdown(shutdown, NULL);
+	struct raiden_debug_spi_data *data = calloc(1, sizeof(struct raiden_debug_spi_data));
+	if (!data) {
+		msg_perr("Unable to allocate space for extra SPI master data.\n");
+		return SPI_GENERIC_ERROR;
+	}
+
+	data->dev = device;
+	data->in_ep = in_endpoint;
+	data->out_ep = out_endpoint;
+
+	register_raiden_debug_spi_master(data);
+	register_shutdown(raiden_debug_spi_shutdown, data);

return 0;
 }