diff options
Diffstat (limited to 'drivers/serial/serial_stm32x7.c')
-rw-r--r-- | drivers/serial/serial_stm32x7.c | 83 |
1 files changed, 83 insertions, 0 deletions
diff --git a/drivers/serial/serial_stm32x7.c b/drivers/serial/serial_stm32x7.c new file mode 100644 index 0000000000..cfbfab7e41 --- /dev/null +++ b/drivers/serial/serial_stm32x7.c @@ -0,0 +1,83 @@ +/* + * (C) Copyright 2016 + * Vikas Manocha, <vikas.manocha@st.com> + * + * SPDX-License-Identifier: GPL-2.0+ + */ + +#include <common.h> +#include <dm.h> +#include <asm/io.h> +#include <serial.h> +#include <dm/platform_data/serial_stm32x7.h> +#include "serial_stm32x7.h" + +DECLARE_GLOBAL_DATA_PTR; + +static int stm32_serial_setbrg(struct udevice *dev, int baudrate) +{ + struct stm32x7_serial_platdata *plat = dev->platdata; + struct stm32_usart *const usart = plat->base; + writel(plat->clock/baudrate, &usart->brr); + + return 0; +} + +static int stm32_serial_getc(struct udevice *dev) +{ + struct stm32x7_serial_platdata *plat = dev->platdata; + struct stm32_usart *const usart = plat->base; + + if ((readl(&usart->sr) & USART_SR_FLAG_RXNE) == 0) + return -EAGAIN; + + return readl(&usart->rd_dr); +} + +static int stm32_serial_putc(struct udevice *dev, const char c) +{ + struct stm32x7_serial_platdata *plat = dev->platdata; + struct stm32_usart *const usart = plat->base; + + if ((readl(&usart->sr) & USART_SR_FLAG_TXE) == 0) + return -EAGAIN; + + writel(c, &usart->tx_dr); + + return 0; +} + +static int stm32_serial_pending(struct udevice *dev, bool input) +{ + struct stm32x7_serial_platdata *plat = dev->platdata; + struct stm32_usart *const usart = plat->base; + + if (input) + return readl(&usart->sr) & USART_SR_FLAG_RXNE ? 1 : 0; + else + return readl(&usart->sr) & USART_SR_FLAG_TXE ? 0 : 1; +} + +static int stm32_serial_probe(struct udevice *dev) +{ + struct stm32x7_serial_platdata *plat = dev->platdata; + struct stm32_usart *const usart = plat->base; + setbits_le32(&usart->cr1, USART_CR1_RE | USART_CR1_TE | USART_CR1_UE); + + return 0; +} + +static const struct dm_serial_ops stm32_serial_ops = { + .putc = stm32_serial_putc, + .pending = stm32_serial_pending, + .getc = stm32_serial_getc, + .setbrg = stm32_serial_setbrg, +}; + +U_BOOT_DRIVER(serial_stm32) = { + .name = "serial_stm32x7", + .id = UCLASS_SERIAL, + .ops = &stm32_serial_ops, + .probe = stm32_serial_probe, + .flags = DM_FLAG_PRE_RELOC, +}; |