Re: [PATCH 2/3] tty/serial: atmel: add ISO7816 support
On Wed, Jul 11, 2018 at 03:16:37PM +0200, Ludovic Desroches wrote: > From: Nicolas Ferre > > 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. > Report NACK and ITER errors in irq handler. > > Signed-off-by: Nicolas Ferre > [ludovic.desroc...@microchip.com: rebase, add check on fidi ratio, checkpatch > fixes] > Signed-off-by: Ludovic Desroches > --- > drivers/tty/serial/atmel_serial.c | 175 > +++--- > drivers/tty/serial/atmel_serial.h | 3 +- > 2 files changed, 167 insertions(+), 11 deletions(-) > > diff --git a/drivers/tty/serial/atmel_serial.c > b/drivers/tty/serial/atmel_serial.c > index 8e4428725848..0118b219f3a8 100644 > --- a/drivers/tty/serial/atmel_serial.c > +++ b/drivers/tty/serial/atmel_serial.c > @@ -34,6 +34,7 @@ > #include > #include > > +#include > #include > #include > > @@ -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 inttx_done_mask; > u32 fifo_size; > u32 rts_high; > @@ -362,6 +365,136 @@ 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); > + dev_dbg(port->dev, "ISO7816 mck_rate = %lld\n", mck_rate); > + do_div(mck_rate, iso7816conf->clk); > + cd = mck_rate; > + dev_dbg(port->dev, "ISO7816 clk = %d. CD = %d\n", iso7816conf->clk, cd); > + return cd; > +} > + > +static unsigned int atmel_calc_fidi(struct uart_port *port, > + struct serial_iso7816 *iso7816conf) > +{ > + u64 fidi = 0; > + > + dev_dbg(port->dev, "ISO7816 fi(%d) / di(%d)\n", > + iso7816conf->sc_fi, iso7816conf->sc_di); Do you still need all of the debugging code? Shouldn't ftrace give you all of this? > + if (iso7816conf->sc_fi && iso7816conf->sc_di) { > + fidi = (u64)iso7816conf->sc_fi; > + do_div(fidi, iso7816conf->sc_di); > + } > + dev_dbg(port->dev, "ISO7816 fidi = 0x%x\n", (u32)fidi); > + 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, t; > + unsigned int cd, fidi; > + int ret = 0; > + > + /* Disable RX and TX */ > + atmel_uart_writel(port, ATMEL_US_CR, ATMEL_US_RXDIS | ATMEL_US_TXDIS); > + /* Disable interrupts */ > + atmel_uart_writel(port, ATMEL_US_IDR, atmel_port->tx_done_mask); > + > + mode = atmel_uart_readl(port, ATMEL_US_MR); > + > + if (!(port->iso7816.flags & SER_ISO7816_ENABLED)) { > + /* port not yet in iso7816 mode: store configuration */ > + atmel_port->backup_mode = mode; > + atmel_port->backup_brgr = atmel_uart_readl(port, ATMEL_US_BRGR); > + } Are you really validating all of the fields in this structure for valid values correctly? It feels like you are missing some here... > @@ -1281,6 +1417,9 @@ 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_err(port->dev, "ISO7816 ERROR (0x%08x)\n", pending); What can someone do with this? If nothing, then why check or tell the user about it? They will ignore it :( thanks, greg k-h
[PATCH 2/3] tty/serial: atmel: add ISO7816 support
From: Nicolas Ferre 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. Report NACK and ITER errors in irq handler. Signed-off-by: Nicolas Ferre [ludovic.desroc...@microchip.com: rebase, add check on fidi ratio, checkpatch fixes] Signed-off-by: Ludovic Desroches --- drivers/tty/serial/atmel_serial.c | 175 +++--- drivers/tty/serial/atmel_serial.h | 3 +- 2 files changed, 167 insertions(+), 11 deletions(-) diff --git a/drivers/tty/serial/atmel_serial.c b/drivers/tty/serial/atmel_serial.c index 8e4428725848..0118b219f3a8 100644 --- a/drivers/tty/serial/atmel_serial.c +++ b/drivers/tty/serial/atmel_serial.c @@ -34,6 +34,7 @@ #include #include +#include #include #include @@ -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 inttx_done_mask; u32 fifo_size; u32 rts_high; @@ -362,6 +365,136 @@ 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); + dev_dbg(port->dev, "ISO7816 mck_rate = %lld\n", mck_rate); + do_div(mck_rate, iso7816conf->clk); + cd = mck_rate; + dev_dbg(port->dev, "ISO7816 clk = %d. CD = %d\n", iso7816conf->clk, cd); + return cd; +} + +static unsigned int atmel_calc_fidi(struct uart_port *port, + struct serial_iso7816 *iso7816conf) +{ + u64 fidi = 0; + + dev_dbg(port->dev, "ISO7816 fi(%d) / di(%d)\n", + iso7816conf->sc_fi, iso7816conf->sc_di); + if (iso7816conf->sc_fi && iso7816conf->sc_di) { + fidi = (u64)iso7816conf->sc_fi; + do_div(fidi, iso7816conf->sc_di); + } + dev_dbg(port->dev, "ISO7816 fidi = 0x%x\n", (u32)fidi); + 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, t; + unsigned int cd, fidi; + int ret = 0; + + /* Disable RX and TX */ + atmel_uart_writel(port, ATMEL_US_CR, ATMEL_US_RXDIS | ATMEL_US_TXDIS); + /* Disable interrupts */ + atmel_uart_writel(port, ATMEL_US_IDR, atmel_port->tx_done_mask); + + mode = atmel_uart_readl(port, ATMEL_US_MR); + + if (!(port->iso7816.flags & SER_ISO7816_ENABLED)) { + /* port not yet in iso7816 mode: store configuration */ + atmel_port->backup_mode = mode; + atmel_port->backup_brgr = atmel_uart_readl(port, ATMEL_US_BRGR); + } + + if (iso7816conf->flags & SER_ISO7816_ENABLED) { + mode &= ~ATMEL_US_USMODE; + + if ((iso7816conf->flags & SER_ISO7816_T_PARAM) + == SER_ISO7816_T(0)) { + mode |= ATMEL_US_USMODE_ISO7816_T0; + t = 0; + } else if ((iso7816conf->flags & SER_ISO7816_T_PARAM) + == SER_ISO7816_T(1)) { + mode |= ATMEL_US_USMODE_ISO7816_T1; + t = 1; + } else { + dev_warn(port->dev, "ISO7816 Type not supported. Resetting\n"); + memset(iso7816conf, 0, sizeof(struct serial_iso7816)); + goto err_out; + } + + dev_dbg(port->dev, "Setting USART to ISO7816 mode T%d\n", t); + + mode &= ~(ATMEL_US_USCLKS | ATMEL_US_CHRL + | ATMEL_US_NBSTOP | ATMEL_US_PAR); + + /* NACK configuration */ + if ((iso7816conf->flags & SER_ISO7816_T_PARAM) + == SER_ISO7816_T(0)) + mode |= ATMEL_US_DSNACK; + else + mode |= ATMEL_US_INACK; + /* 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 | (3 << 24); + + cd = atmel_calc_cd(port, iso7