From mboxrd@z Thu Jan 1 00:00:00 1970 Message-ID: <4F04589A.5090404@domain.hid> Date: Wed, 04 Jan 2012 14:48:10 +0100 From: Fabrice Gasnier MIME-Version: 1.0 Content-Type: multipart/mixed; boundary="------------090506010205040304070409" Subject: Re: [Xenomai-help] Xenomai rtcan build issue on MPC5121 (kernel >= 2.6.35) List-Id: Help regarding installation and common use of Xenomai List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , To: wg@domain.hid, xenomai@xenomai.org This is a multi-part message in MIME format. --------------090506010205040304070409 Content-Type: text/plain; charset=ISO-8859-1; format=flowed Content-Transfer-Encoding: 7bit --- ksrc/drivers/can/mscan/rtcan_mscan.c | 38 ++++++++++++++++++++++++++++++++- 1 files changed, 36 insertions(+), 2 deletions(-) --------------090506010205040304070409 Content-Type: text/x-patch; name="0001-fix-mscan-init-on-mpc5121.patch" Content-Transfer-Encoding: 7bit Content-Disposition: attachment; filename="0001-fix-mscan-init-on-mpc5121.patch" diff --git a/ksrc/drivers/can/mscan/rtcan_mscan.c b/ksrc/drivers/can/mscan/rtcan_mscan.c index d25fc5a..edd590e 100644 --- a/ksrc/drivers/can/mscan/rtcan_mscan.c +++ b/ksrc/drivers/can/mscan/rtcan_mscan.c @@ -40,6 +40,8 @@ #include "rtcan_mscan_regs.h" #include "rtcan_mscan.h" +#define MSCAN_SET_MODE_RETRIES 255 + /** * Reception Interrupt handler * @@ -306,11 +308,41 @@ static int rtcan_mscan_mode_stop(struct rtcan_device *dev, /* Switch to sleep mode */ setbits8(®s->canctl0, MSCAN_SLPRQ); + reg = in_8(®s->canctl1); + while (!(reg & MSCAN_SLPAK) && + (rinit < MSCAN_SET_MODE_RETRIES)) { + if (likely(lock_ctx != NULL)) + rtdm_lock_put_irqrestore(&dev->device_lock, *lock_ctx); + /* Busy sleep 1 microsecond */ + rtdm_task_busy_sleep(1000); + if (likely(lock_ctx != NULL)) + rtdm_lock_get_irqsave(&dev->device_lock, *lock_ctx); + rinit++; + reg = in_8(®s->canctl1); + } + /* + * The mscan controller will fail to enter sleep mode, + * while there are irregular activities on bus, like + * somebody keeps retransmitting. This behavior is + * undocumented and seems to differ between mscan built + * in mpc5200b and mpc5200. We proceed in that case, + * since otherwise the slprq will be kept set and the + * controller will get stuck. NOTE: INITRQ or CSWAI + * will abort all active transmit actions, if still + * any, at once. + */ + if (rinit >= MSCAN_SET_MODE_RETRIES) + rtdm_printk("rtcan_mscan: device failed to enter sleep mode. " + "We proceed anyhow.\n"); + else + dev->state = CAN_STATE_SLEEPING; + + rinit = 0; setbits8(®s->canctl0, MSCAN_INITRQ); reg = in_8(®s->canctl1); - while (!(reg & MSCAN_SLPAK) || - !(reg & MSCAN_INITAK)) { + while (!(reg & MSCAN_INITAK) && + (rinit < MSCAN_SET_MODE_RETRIES)) { if (likely(lock_ctx != NULL)) rtdm_lock_put_irqrestore(&dev->device_lock, *lock_ctx); /* Busy sleep 1 microsecond */ @@ -320,6 +352,8 @@ static int rtcan_mscan_mode_stop(struct rtcan_device *dev, rinit++; reg = in_8(®s->canctl1); } + if (rinit >= MSCAN_SET_MODE_RETRIES) + ret = -ENODEV; /* Volatile state could have changed while we slept busy. */ dev->state = CAN_STATE_STOPPED; --------------090506010205040304070409--