diff options
| -rw-r--r-- | mcp6x_spi.c | 79 |
1 files changed, 56 insertions, 23 deletions
diff --git a/mcp6x_spi.c b/mcp6x_spi.c index de442994..fa309ca3 100644 --- a/mcp6x_spi.c +++ b/mcp6x_spi.c @@ -36,55 +36,68 @@ #define MCP6X_SPI_REQUEST 0 #define MCP6X_SPI_GRANT 8 -static void *mcp6x_spibar = NULL; - -/* Cached value of last GPIO state. */ -static uint8_t mcp_gpiostate; +struct mcp6x_spi_data { + void *spibar; + /* Cached value of last GPIO state. */ + uint8_t gpiostate; +}; static void mcp6x_request_spibus(void *spi_data) { - mcp_gpiostate = mmio_readb(mcp6x_spibar + 0x530); - mcp_gpiostate |= 1 << MCP6X_SPI_REQUEST; - mmio_writeb(mcp_gpiostate, mcp6x_spibar + 0x530); + struct mcp6x_spi_data *data = spi_data; + + data->gpiostate = mmio_readb(data->spibar + 0x530); + data->gpiostate |= 1 << MCP6X_SPI_REQUEST; + mmio_writeb(data->gpiostate, data->spibar + 0x530); /* Wait until we are allowed to use the SPI bus. */ - while (!(mmio_readw(mcp6x_spibar + 0x530) & (1 << MCP6X_SPI_GRANT))) ; + while (!(mmio_readw(data->spibar + 0x530) & (1 << MCP6X_SPI_GRANT))) ; /* Update the cache. */ - mcp_gpiostate = mmio_readb(mcp6x_spibar + 0x530); + data->gpiostate = mmio_readb(data->spibar + 0x530); } static void mcp6x_release_spibus(void *spi_data) { - mcp_gpiostate &= ~(1 << MCP6X_SPI_REQUEST); - mmio_writeb(mcp_gpiostate, mcp6x_spibar + 0x530); + struct mcp6x_spi_data *data = spi_data; + + data->gpiostate &= ~(1 << MCP6X_SPI_REQUEST); + mmio_writeb(data->gpiostate, data->spibar + 0x530); } static void mcp6x_bitbang_set_cs(int val, void *spi_data) { - mcp_gpiostate &= ~(1 << MCP6X_SPI_CS); - mcp_gpiostate |= (val << MCP6X_SPI_CS); - mmio_writeb(mcp_gpiostate, mcp6x_spibar + 0x530); + struct mcp6x_spi_data *data = spi_data; + + data->gpiostate &= ~(1 << MCP6X_SPI_CS); + data->gpiostate |= (val << MCP6X_SPI_CS); + mmio_writeb(data->gpiostate, data->spibar + 0x530); } static void mcp6x_bitbang_set_sck(int val, void *spi_data) { - mcp_gpiostate &= ~(1 << MCP6X_SPI_SCK); - mcp_gpiostate |= (val << MCP6X_SPI_SCK); - mmio_writeb(mcp_gpiostate, mcp6x_spibar + 0x530); + struct mcp6x_spi_data *data = spi_data; + + data->gpiostate &= ~(1 << MCP6X_SPI_SCK); + data->gpiostate |= (val << MCP6X_SPI_SCK); + mmio_writeb(data->gpiostate, data->spibar + 0x530); } static void mcp6x_bitbang_set_mosi(int val, void *spi_data) { - mcp_gpiostate &= ~(1 << MCP6X_SPI_MOSI); - mcp_gpiostate |= (val << MCP6X_SPI_MOSI); - mmio_writeb(mcp_gpiostate, mcp6x_spibar + 0x530); + struct mcp6x_spi_data *data = spi_data; + + data->gpiostate &= ~(1 << MCP6X_SPI_MOSI); + data->gpiostate |= (val << MCP6X_SPI_MOSI); + mmio_writeb(data->gpiostate, data->spibar + 0x530); } static int mcp6x_bitbang_get_miso(void *spi_data) { - mcp_gpiostate = mmio_readb(mcp6x_spibar + 0x530); - return (mcp_gpiostate >> MCP6X_SPI_MISO) & 0x1; + struct mcp6x_spi_data *data = spi_data; + + data->gpiostate = mmio_readb(data->spibar + 0x530); + return (data->gpiostate >> MCP6X_SPI_MISO) & 0x1; } static const struct bitbang_spi_master bitbang_spi_master_mcp6x = { @@ -97,11 +110,19 @@ static const struct bitbang_spi_master bitbang_spi_master_mcp6x = { .half_period = 0, }; +static int mcp6x_shutdown(void *spi_data) +{ + free(spi_data); + return 0; +} + int mcp6x_spi_init(int want_spi) { uint16_t status; uint32_t mcp6x_spibaraddr; struct pci_dev *smbusdev; + void *mcp6x_spibar = NULL; + uint8_t mcp_gpiostate; /* Look for the SMBus device (SMBus PCI class) */ smbusdev = pci_dev_find_vendorclass(0x10de, 0x0c05); @@ -151,7 +172,19 @@ int mcp6x_spi_init(int want_spi) (status >> MCP6X_SPI_GRANT) & 0x1); mcp_gpiostate = status & 0xff; - if (register_spi_bitbang_master(&bitbang_spi_master_mcp6x, NULL)) { + struct mcp6x_spi_data *data = calloc(1, sizeof(*data)); + if (!data) { + msg_perr("Unable to allocate space for SPI master data\n"); + return 1; + } + data->spibar = mcp6x_spibar; + data->gpiostate = mcp_gpiostate; + + if (register_shutdown(mcp6x_shutdown, data)) { + free(data); + return 1; + } + if (register_spi_bitbang_master(&bitbang_spi_master_mcp6x, data)) { /* This should never happen. */ msg_perr("MCP6X bitbang SPI master init failed!\n"); return 1; |