diff options
author | 2018-09-26 14:58:48 +0200 | |
---|---|---|
committer | 2018-10-02 13:38:55 -0700 | |
commit | 377fedd1866ae3979e4fe36193475b8acbc82784 (patch) | |
tree | f7af5d413eb92eb10d5f6c5c5d90d9dda1410a14 /drivers/tty | |
parent | tty/serial_core: add ISO7816 infrastructure (diff) | |
download | linux-377fedd1866ae3979e4fe36193475b8acbc82784.tar.gz linux-377fedd1866ae3979e4fe36193475b8acbc82784.tar.bz2 linux-377fedd1866ae3979e4fe36193475b8acbc82784.zip |
tty/serial: atmel: add ISO7816 support
When mode is set in atmel_config_iso7816() we backup last RS232 mode
for coming back to this mode if requested.
Also allow setup of T=0 and T=1 parameter and basic support in set_termios
function as well.
Signed-off-by: Nicolas Ferre <nicolas.ferre@microchip.com>
[ludovic.desroches@microchip.com: rebase, add check on fidi ratio, checkpatch fixes]
Signed-off-by: Ludovic Desroches <ludovic.desroches@microchip.com>
Acked-by: Richard Genoud <richard.genoud@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Diffstat (limited to 'drivers/tty')
-rw-r--r-- | drivers/tty/serial/atmel_serial.c | 190 | ||||
-rw-r--r-- | drivers/tty/serial/atmel_serial.h | 3 |
2 files changed, 181 insertions, 12 deletions
diff --git a/drivers/tty/serial/atmel_serial.c b/drivers/tty/serial/atmel_serial.c index 267d4d1de3f8..05147fe24343 100644 --- a/drivers/tty/serial/atmel_serial.c +++ b/drivers/tty/serial/atmel_serial.c @@ -34,6 +34,7 @@ #include <linux/suspend.h> #include <linux/mm.h> +#include <asm/div64.h> #include <asm/io.h> #include <asm/ioctls.h> @@ -147,6 +148,8 @@ struct atmel_uart_port { struct circ_buf rx_ring; struct mctrl_gpios *gpios; + u32 backup_mode; /* MR saved during iso7816 operations */ + u32 backup_brgr; /* BRGR saved during iso7816 operations */ unsigned int tx_done_mask; u32 fifo_size; u32 rts_high; @@ -163,6 +166,10 @@ struct atmel_uart_port { unsigned int pending_status; spinlock_t lock_suspended; + /* ISO7816 */ + unsigned int fidi_min; + unsigned int fidi_max; + #ifdef CONFIG_PM struct { u32 cr; @@ -361,6 +368,127 @@ static int atmel_config_rs485(struct uart_port *port, return 0; } +static unsigned int atmel_calc_cd(struct uart_port *port, + struct serial_iso7816 *iso7816conf) +{ + struct atmel_uart_port *atmel_port = to_atmel_uart_port(port); + unsigned int cd; + u64 mck_rate; + + mck_rate = (u64)clk_get_rate(atmel_port->clk); + do_div(mck_rate, iso7816conf->clk); + cd = mck_rate; + return cd; +} + +static unsigned int atmel_calc_fidi(struct uart_port *port, + struct serial_iso7816 *iso7816conf) +{ + u64 fidi = 0; + + if (iso7816conf->sc_fi && iso7816conf->sc_di) { + fidi = (u64)iso7816conf->sc_fi; + do_div(fidi, iso7816conf->sc_di); + } + return (u32)fidi; +} + +/* Enable or disable the iso7816 support */ +/* Called with interrupts disabled */ +static int atmel_config_iso7816(struct uart_port *port, + struct serial_iso7816 *iso7816conf) +{ + struct atmel_uart_port *atmel_port = to_atmel_uart_port(port); + unsigned int mode; + unsigned int cd, fidi; + int ret = 0; + + /* Disable interrupts */ + atmel_uart_writel(port, ATMEL_US_IDR, atmel_port->tx_done_mask); + + mode = atmel_uart_readl(port, ATMEL_US_MR); + + if (iso7816conf->flags & SER_ISO7816_ENABLED) { + mode &= ~ATMEL_US_USMODE; + + if (iso7816conf->tg > 255) { + dev_err(port->dev, "ISO7816: Timeguard exceeding 255\n"); + memset(iso7816conf, 0, sizeof(struct serial_iso7816)); + ret = -EINVAL; + goto err_out; + } + + if ((iso7816conf->flags & SER_ISO7816_T_PARAM) + == SER_ISO7816_T(0)) { + mode |= ATMEL_US_USMODE_ISO7816_T0 | ATMEL_US_DSNACK; + } else if ((iso7816conf->flags & SER_ISO7816_T_PARAM) + == SER_ISO7816_T(1)) { + mode |= ATMEL_US_USMODE_ISO7816_T1 | ATMEL_US_INACK; + } else { + dev_err(port->dev, "ISO7816: Type not supported\n"); + memset(iso7816conf, 0, sizeof(struct serial_iso7816)); + ret = -EINVAL; + goto err_out; + } + + mode &= ~(ATMEL_US_USCLKS | ATMEL_US_NBSTOP | ATMEL_US_PAR); + + /* select mck clock, and output */ + mode |= ATMEL_US_USCLKS_MCK | ATMEL_US_CLKO; + /* set parity for normal/inverse mode + max iterations */ + mode |= ATMEL_US_PAR_EVEN | ATMEL_US_NBSTOP_1 | ATMEL_US_MAX_ITER(3); + + cd = atmel_calc_cd(port, iso7816conf); + fidi = atmel_calc_fidi(port, iso7816conf); + if (fidi == 0) { + dev_warn(port->dev, "ISO7816 fidi = 0, Generator generates no signal\n"); + } else if (fidi < atmel_port->fidi_min + || fidi > atmel_port->fidi_max) { + dev_err(port->dev, "ISO7816 fidi = %u, value not supported\n", fidi); + memset(iso7816conf, 0, sizeof(struct serial_iso7816)); + ret = -EINVAL; + goto err_out; + } + + if (!(port->iso7816.flags & SER_ISO7816_ENABLED)) { + /* port not yet in iso7816 mode: store configuration */ + atmel_port->backup_mode = atmel_uart_readl(port, ATMEL_US_MR); + atmel_port->backup_brgr = atmel_uart_readl(port, ATMEL_US_BRGR); + } + + atmel_uart_writel(port, ATMEL_US_TTGR, iso7816conf->tg); + atmel_uart_writel(port, ATMEL_US_BRGR, cd); + atmel_uart_writel(port, ATMEL_US_FIDI, fidi); + + atmel_uart_writel(port, ATMEL_US_CR, ATMEL_US_TXDIS | ATMEL_US_RXEN); + atmel_port->tx_done_mask = ATMEL_US_TXEMPTY | ATMEL_US_NACK | ATMEL_US_ITERATION; + } else { + dev_dbg(port->dev, "Setting UART back to RS232\n"); + /* back to last RS232 settings */ + mode = atmel_port->backup_mode; + memset(iso7816conf, 0, sizeof(struct serial_iso7816)); + atmel_uart_writel(port, ATMEL_US_TTGR, 0); + atmel_uart_writel(port, ATMEL_US_BRGR, atmel_port->backup_brgr); + atmel_uart_writel(port, ATMEL_US_FIDI, 0x174); + + if (atmel_use_pdc_tx(port)) + atmel_port->tx_done_mask = ATMEL_US_ENDTX | + ATMEL_US_TXBUFE; + else + atmel_port->tx_done_mask = ATMEL_US_TXRDY; + } + + port->iso7816 = *iso7816conf; + + atmel_uart_writel(port, ATMEL_US_MR, mode); + +err_out: + /* Enable interrupts */ + atmel_uart_writel(port, ATMEL_US_IER, atmel_port->tx_done_mask); + + return ret; +} + /* * Return TIOCSER_TEMT when transmitter FIFO and Shift register is empty. */ @@ -480,8 +608,9 @@ static void atmel_stop_tx(struct uart_port *port) /* Disable interrupts */ atmel_uart_writel(port, ATMEL_US_IDR, atmel_port->tx_done_mask); - if ((port->rs485.flags & SER_RS485_ENABLED) && - !(port->rs485.flags & SER_RS485_RX_DURING_TX)) + if (((port->rs485.flags & SER_RS485_ENABLED) && + !(port->rs485.flags & SER_RS485_RX_DURING_TX)) || + port->iso7816.flags & SER_ISO7816_ENABLED) atmel_start_rx(port); } @@ -499,8 +628,9 @@ static void atmel_start_tx(struct uart_port *port) return; if (atmel_use_pdc_tx(port) || atmel_use_dma_tx(port)) - if ((port->rs485.flags & SER_RS485_ENABLED) && - !(port->rs485.flags & SER_RS485_RX_DURING_TX)) + if (((port->rs485.flags & SER_RS485_ENABLED) && + !(port->rs485.flags & SER_RS485_RX_DURING_TX)) || + port->iso7816.flags & SER_ISO7816_ENABLED) atmel_stop_rx(port); if (atmel_use_pdc_tx(port)) @@ -798,8 +928,9 @@ static void atmel_complete_tx_dma(void *arg) */ if (!uart_circ_empty(xmit)) atmel_tasklet_schedule(atmel_port, &atmel_port->tasklet_tx); - else if ((port->rs485.flags & SER_RS485_ENABLED) && - !(port->rs485.flags & SER_RS485_RX_DURING_TX)) { + else if (((port->rs485.flags & SER_RS485_ENABLED) && + !(port->rs485.flags & SER_RS485_RX_DURING_TX)) || + port->iso7816.flags & SER_ISO7816_ENABLED) { /* DMA done, stop TX, start RX for RS485 */ atmel_start_rx(port); } @@ -1282,6 +1413,9 @@ atmel_handle_status(struct uart_port *port, unsigned int pending, wake_up_interruptible(&port->state->port.delta_msr_wait); } } + + if (pending & (ATMEL_US_NACK | ATMEL_US_ITERATION)) + dev_dbg(port->dev, "ISO7816 ERROR (0x%08x)\n", pending); } /* @@ -1374,8 +1508,9 @@ static void atmel_tx_pdc(struct uart_port *port) atmel_uart_writel(port, ATMEL_US_IER, atmel_port->tx_done_mask); } else { - if ((port->rs485.flags & SER_RS485_ENABLED) && - !(port->rs485.flags & SER_RS485_RX_DURING_TX)) { + if (((port->rs485.flags & SER_RS485_ENABLED) && + !(port->rs485.flags & SER_RS485_RX_DURING_TX)) || + port->iso7816.flags & SER_ISO7816_ENABLED) { /* DMA done, stop TX, start RX for RS485 */ atmel_start_rx(port); } @@ -1727,6 +1862,22 @@ static void atmel_get_ip_name(struct uart_port *port) atmel_port->has_frac_baudrate = true; atmel_port->has_hw_timer = true; atmel_port->rtor = ATMEL_US_RTOR; + version = atmel_uart_readl(port, ATMEL_US_VERSION); + switch (version) { + case 0x814: /* sama5d2 */ + /* fall through */ + case 0x701: /* sama5d4 */ + atmel_port->fidi_min = 3; + atmel_port->fidi_max = 65535; + break; + case 0x502: /* sam9x5, sama5d3 */ + atmel_port->fidi_min = 3; + atmel_port->fidi_max = 2047; + break; + default: + atmel_port->fidi_min = 1; + atmel_port->fidi_max = 2047; + } } else if (name == dbgu_uart) { dev_dbg(port->dev, "Dbgu or uart without hw timer\n"); } else { @@ -2100,6 +2251,17 @@ static void atmel_set_termios(struct uart_port *port, struct ktermios *termios, atmel_uart_writel(port, ATMEL_US_TTGR, port->rs485.delay_rts_after_send); mode |= ATMEL_US_USMODE_RS485; + } else if (port->iso7816.flags & SER_ISO7816_ENABLED) { + atmel_uart_writel(port, ATMEL_US_TTGR, port->iso7816.tg); + /* select mck clock, and output */ + mode |= ATMEL_US_USCLKS_MCK | ATMEL_US_CLKO; + /* set max iterations */ + mode |= ATMEL_US_MAX_ITER(3); + if ((port->iso7816.flags & SER_ISO7816_T_PARAM) + == SER_ISO7816_T(0)) + mode |= ATMEL_US_USMODE_ISO7816_T0; + else + mode |= ATMEL_US_USMODE_ISO7816_T1; } else if (termios->c_cflag & CRTSCTS) { /* RS232 with hardware handshake (RTS/CTS) */ if (atmel_use_fifo(port) && @@ -2176,7 +2338,8 @@ static void atmel_set_termios(struct uart_port *port, struct ktermios *termios, } quot = cd | fp << ATMEL_US_FP_OFFSET; - atmel_uart_writel(port, ATMEL_US_BRGR, quot); + if (!(port->iso7816.flags & SER_ISO7816_ENABLED)) + atmel_uart_writel(port, ATMEL_US_BRGR, quot); atmel_uart_writel(port, ATMEL_US_CR, ATMEL_US_RSTSTA | ATMEL_US_RSTRX); atmel_uart_writel(port, ATMEL_US_CR, ATMEL_US_TXEN | ATMEL_US_RXEN); atmel_port->tx_stopped = false; @@ -2357,6 +2520,7 @@ static int atmel_init_port(struct atmel_uart_port *atmel_port, port->mapbase = mpdev->resource[0].start; port->irq = mpdev->resource[1].start; port->rs485_config = atmel_config_rs485; + port->iso7816_config = atmel_config_iso7816; port->membase = NULL; memset(&atmel_port->rx_ring, 0, sizeof(atmel_port->rx_ring)); @@ -2380,8 +2544,12 @@ static int atmel_init_port(struct atmel_uart_port *atmel_port, /* only enable clock when USART is in use */ } - /* Use TXEMPTY for interrupt when rs485 else TXRDY or ENDTX|TXBUFE */ - if (port->rs485.flags & SER_RS485_ENABLED) + /* + * Use TXEMPTY for interrupt when rs485 or ISO7816 else TXRDY or + * ENDTX|TXBUFE + */ + if (port->rs485.flags & SER_RS485_ENABLED || + port->iso7816.flags & SER_ISO7816_ENABLED) atmel_port->tx_done_mask = ATMEL_US_TXEMPTY; else if (atmel_use_pdc_tx(port)) { port->fifosize = PDC_BUFFER_SIZE; diff --git a/drivers/tty/serial/atmel_serial.h b/drivers/tty/serial/atmel_serial.h index ba3a2437cde4..d811d4f2d0c0 100644 --- a/drivers/tty/serial/atmel_serial.h +++ b/drivers/tty/serial/atmel_serial.h @@ -78,7 +78,8 @@ #define ATMEL_US_OVER BIT(19) /* Oversampling Mode */ #define ATMEL_US_INACK BIT(20) /* Inhibit Non Acknowledge */ #define ATMEL_US_DSNACK BIT(21) /* Disable Successive NACK */ -#define ATMEL_US_MAX_ITER GENMASK(26, 24) /* Max Iterations */ +#define ATMEL_US_MAX_ITER_MASK GENMASK(26, 24) /* Max Iterations */ +#define ATMEL_US_MAX_ITER(n) (((n) << 24) & ATMEL_US_MAX_ITER_MASK) #define ATMEL_US_FILTER BIT(28) /* Infrared Receive Line Filter */ #define ATMEL_US_IER 0x08 /* Interrupt Enable Register */ |